Cherry Marshmallow Swiss Roll
Prep. Time:
40 minutes
Baking Time:
10–12 minutes
Total Time:
Approximately 2 hours (including chilling)
Serves:
1 large Swiss roll (10–12 slices)
Iain Ross's Fift-Queen's University Swiss Roll threads the beloved flavors of Northern Irish Fifteens — digestive biscuits, glacé cherries, marshmallows, and coconut — through an elegant Swiss roll sponge. The digestive biscuit crumbs folded into the sponge batter provide a distinctive malty, buttery base, while a cherry compote made from both glacé and fresh cherries adds jewel-like tartness and the marshmallow cream filling delivers the signature chewy sweetness of a Fifteen without the condensed milk. Paul Hollywood called it one mighty impressive Swiss roll with stunning flavors, noting that leaving out the condensed milk was a smart decision that kept the sweetness perfectly balanced. This enhanced recipe addresses the oval cross-section Paul noted by emphasizing full ribbon-stage egg aeration and medium-stiff cream peaks for structural integrity.
Chef's Notes: Addressing Judge Feedback
"It's sat down on itself - it's a wee bit of an oval" - Paul Hollywood
The oval cross-section Paul noted is one of the most common Swiss roll pitfalls, and it comes down to two factors working against the baker: insufficient egg aeration in the sponge, and/or a filling that's too soft to support the structure. When the egg-sugar mixture isn't beaten to full ribbon stage, the sponge lacks the air cell structure needed to maintain its spring after rolling. Under gravity, it slowly flattens from a circle into an ellipse. The second culprit is a filling that's too loose - whipped cream at soft peaks will slowly compress under the weight of the sponge layers above it.
This recipe addresses both issues. The eggs are beaten for a full 5–7 minutes to maximum volume, and the cream is whipped to medium-stiff peaks before the marshmallow fluff is folded in. Rolling from the short end (rather than the long end) also helps, as it produces a taller roll with more structural layers in the spiral. Finally, wrapping snugly and chilling allows everything to set firmly into shape.
"The flavors are stunning... I was nervous the marshmallow and the jam would make it all too sweet, but it's delicious. You left the condensed milk out. I'm glad you did." - Paul Hollywood
The traditional Fifteen is unabashedly sweet - condensed milk binding together marshmallows, glacé cherries, and crushed digestives is a full-throttle sugar experience. Iain's brilliant insight was recognizing that a Swiss roll already contains sugar in the sponge, so the condensed milk binder would push the whole thing over the edge. Instead, the marshmallow cream filling provides the Fifteen's signature chewy sweetness while the whipped cream and cherry compote add richness and tartness that keep everything in balance. The lemon juice in the compote is essential - it cuts through the sweetness and brightens the cherry flavor, preventing the one-note sugar bomb that Paul feared.
The Inlay Design: While we've excluded the architectural inlay from this recipe (that's a masterclass in its own right), it's worth noting that Paul called Iain's rendering of Queen's University Belfast's Lanyon Building "extremely impressive" and "amazing." For a baker who admits precision isn't his strongest suit, the level of detail was remarkable. As Iain himself put it about his baking style: "Anything that requires something to look cool or fun is perfect for me." The inlay alone would have made this Swiss roll memorable, but it was the combination of visual ambition and genuinely delicious Fifteen-inspired flavors that made it a standout in a very strong first week.
Troubleshooting
Sponge cracks when rolling: The sponge was overbaked or cooled too much before the initial roll. Roll immediately out of the oven while still hot and pliable. If you see the surface drying out before you're ready, cover it with a damp (not wet) towel for 30 seconds.
Roll has an oval shape after chilling: The filling was likely too soft. Ensure cream is whipped to medium-stiff peaks (not soft peaks). When wrapping in plastic, gently cup your hands around the roll to press it into a round shape before twisting the ends. You can also place the wrapped roll inside a paper towel tube cut lengthwise to act as a cradle.
Filling oozes out the ends: Too much filling was used, or it wasn't spread thin enough near the edges. Always leave a 1-inch border on the far edge and taper the filling thickness. If the filling is warm, chill it for 15 minutes before spreading.
Sponge is dense or flat: The eggs weren't beaten long enough. The ribbon stage is non-negotiable - you need a full 5–7 minutes on high speed. Also ensure the dry ingredients were folded in gently; aggressive stirring deflates the batter and you lose the air structure that gives Swiss roll sponge its characteristic lightness.
Digestive pieces visible in sponge: The biscuits weren't crushed finely enough. Process them to a fine powder - any larger pieces will create textural bumps in the thin sponge and can cause cracking.
Marshmallow cream is lumpy: If using melted marshmallows rather than fluff, ensure they're completely cooled to room temperature before folding into the whipped cream. Warm marshmallow will deflate the cream instantly. Marshmallow fluff folds in more smoothly and is the easier option.
Storage
Refrigerator: Store wrapped in plastic wrap or in an airtight container for up to 3 days. The flavors actually improve after a night in the fridge as the digestive biscuit notes in the sponge develop and the cherry compote moistens the layers.
Freezer: Wrap tightly in plastic wrap and then foil. Freeze for up to 1 month. Thaw overnight in the refrigerator. The marshmallow cream may soften slightly upon thawing but the flavor will be unaffected.
Serving: Remove from the refrigerator 10–15 minutes before slicing for the cleanest cuts and best flavor. Cold cream tastes muted; a brief rest brings out the marshmallow sweetness and cherry brightness.
Variations
Chocolate Stout Version: Replace 2 tablespoons of flour with cocoa powder and add 1 tablespoon of stout (like Guinness) to the batter - a nod to Iain's Downhill Beach showstopper cake from the same episode, which paired chocolate stout with blackberry jam and cream cheese.
Full Fifteen Filling: For maximum Fifteen authenticity, fold 2 tablespoons of finely crushed digestive biscuit crumbs into the marshmallow cream along with the coconut. This adds the gritty, crumbly texture of a traditional Fifteen slice.
Pink and White Marshmallow Cream: Use a mix of pink and white marshmallows (or strawberry-flavored fluff) for a color that nods to the traditional Fifteen's signature pink-and-white look. Add a drop of rose water for a subtle floral note.
Condensed Milk Drizzle (for the Bold): If you want to acknowledge the condensed milk that Iain wisely left out, drizzle a thin line of it over the finished roll as decoration only - a tiny, controlled amount that adds visual interest without overwhelming the sweetness balance.
About Northern Irish Fifteens
Fifteens are a no-bake fridge cake and cultural institution in Ulster, named for their beautifully simple ratio: 15 digestive biscuits, 15 marshmallows, and 15 glacé cherries, bound with sweetened condensed milk and rolled in desiccated coconut. No oven is required - you crush, mix, shape into a log, chill, and slice into 15 rounds. They're a staple of bake sales, church halls, and family tins across Northern Ireland and County Donegal, representing the resourceful ingenuity of turning basic pantry staples into something communal and joyful. While largely unknown outside Ulster, Fifteens hold a deep nostalgic significance for Northern Irish people - they are, as one writer described them, a "birthright" for locals. By threading these flavors through an elegant Swiss roll, Iain honored his roots while proving that the simplest traditions can inspire the most creative baking.
Ingredients
Instructions
MAKE THE CHERRY COMPOTE (CAN BE DONE AHEAD):
1. Combine the quartered glacé cherries, chopped fresh or frozen cherries, sugar, lemon juice, and water in a small saucepan over medium heat.
2. Bring to a gentle simmer and cook for 8–10 minutes, stirring occasionally, until the fresh cherries have broken down and the mixture is thick and jammy. The glacé cherries should remain as distinct, jewel-like pieces throughout.
3. Remove from heat and let cool completely. The compote will continue to thicken as it cools. Refrigerate until needed. This can be made up to 3 days in advance.
MAKE THE DIGESTIVE BISCUIT SPONGE:
4. Preheat the oven to 200°C / 400°F. Line a 25 × 38cm (10 × 15-inch) jelly roll pan with parchment paper, leaving a slight overhang on the long sides. Lightly grease the parchment.
5. Crush the digestive biscuits to a fine powder using a food processor or a rolling pin and a sealed bag. No large pieces should remain — they would create weak points in the sponge where it could crack during rolling.
6. Whisk the flour, crushed biscuits, baking powder, and salt together in a bowl. Set aside.
7. In a large bowl or stand mixer with whisk attachment, beat the eggs and caster sugar on high speed for 5–7 minutes until the mixture is very thick, pale, and tripled in volume. When you lift the whisk, the batter should fall in a thick ribbon that holds its shape on the surface for 3–4 seconds before dissolving. This aeration is the single most important step for a Swiss roll that holds its round shape and does not sit down into an oval.
8. Add the vanilla and beat briefly to combine.
9. Fold in the dry ingredients in two additions, using a large metal spoon or flexible spatula. Work gently but confidently — cut down through the center, sweep along the bottom, and fold up and over. Rotate the bowl a quarter turn and repeat. Incorporate the flour mixture completely while deflating the batter as little as possible. The crushed digestive will absorb moisture faster than plain flour, so do not overwork the batter or it will become dense.
10. Fold in the melted butter by drizzling it down the side of the bowl and folding gently — no more than 5–6 strokes.
11. Pour immediately into the prepared pan and spread evenly using an offset spatula, working quickly. Pay special attention to the corners — thin spots will overbake and crack.
12. Bake for 10–12 minutes until the sponge is golden, springs back when lightly pressed, and has just begun to pull away from the edges. Do not overbake — an overbaked sponge will crack when rolled.
ROLL THE SPONGE:
13. While the sponge bakes, lay a clean, lint-free kitchen towel on the counter and dust it generously with caster sugar.
14. As soon as the sponge comes out of the oven, invert it onto the sugared towel. Peel off the parchment paper carefully.
15. Starting from a short end, roll the sponge up tightly together with the towel, creating a spiral with the towel trapped inside. This trains the sponge to hold its rolled shape. Rolling from the short end creates a taller, rounder roll with more visible spirals.
16. Place seam-side down on a wire rack and let cool completely, about 30 minutes. Do not rush this step; a warm sponge will melt the cream filling.
MAKE THE MARSHMALLOW CREAM FILLING:
17. If using mini marshmallows instead of fluff: place marshmallows in a microwave-safe bowl with 1 tablespoon of the cream. Microwave in 15-second bursts, stirring between each, until fully melted and smooth. Let cool to room temperature — the mixture must not be warm when folded into whipped cream.
18. Whip the heavy cream with the powdered sugar and vanilla to medium-stiff peaks. The cream should hold its shape firmly when the whisk is lifted — soft peaks will cause the filling to ooze and the roll to flatten.
19. Fold in the marshmallow fluff (or cooled melted marshmallows) in two additions, using gentle folding motions until just combined. Visible streaks of marshmallow through the cream are desirable — they create pockets of chewy sweetness that recall biting into a Fifteen.
20. Fold in the toasted desiccated coconut for texture and that essential Fifteen flavor note.
ASSEMBLE THE SWISS ROLL:
21. Gently unroll the cooled sponge. Do not worry about slight cracking — the filling will hide it.
22. Spread the cherry compote in a thin, even layer over the sponge, leaving a 2.5cm (1-inch) border along the far short edge to prevent filling from squeezing out when rolled.
23. Spread the marshmallow cream over the compote in an even layer, slightly thicker at the near edge and tapering toward the far edge. Use about three-quarters of the cream. Reserve the remainder for patching or garnishing.
24. Re-roll the sponge tightly from the short end, using the towel to help guide it and applying gentle, even pressure. Peel the towel away as you go. When complete, place seam-side down.
25. Wrap snugly in cling film, gently pressing the roll into a round shape. Twist the ends like a candy wrapper to maintain even pressure.
26. Refrigerate for at least 1 hour, or up to overnight. The chilling time allows the filling to set firmly, which helps the roll hold its round profile.
FINISHING:
27. Unwrap the Swiss roll and trim both ends at a slight angle with a sharp serrated knife for a clean presentation.
28. Transfer to a serving board or plate. Dust lightly with powdered sugar, scatter a few halved glacé cherries along the top, and finish with a light sprinkle of toasted coconut.
29. Slice with a sharp serrated knife, using a gentle sawing motion to preserve the spiral.
