Cheese and Onion Doughnut with Catalan Cream

STEP 1: MAKE THE CRISP MILK

Put the whole milk in a wide pan over a medium-low heat and reduce it by about a third, to roughly 265 g, stirring so it does not catch. Take it off the heat, tip in the cheese and onion crisps, and leave to infuse for 20 minutes. Blitz smooth, then strain hard through a fine mesh sieve, pressing the solids. Cool to blood heat. This makes a little more than the dough needs, and the surplus keeps for three days.

STEP 2: MIX THE DOUGH

Combine the bread flour, caster sugar, yeast and fine sea salt in the bowl of a stand mixer, keeping the yeast and salt on opposite sides. Add 180 g of the cooled crisp milk and the egg. Mix on low to a shaggy dough, then on medium for 6 to 8 minutes until it clears the bowl. Add the soft butter a piece at a time, mixing until each disappears, then work for another 4 to 5 minutes to a smooth, elastic, slightly tacky dough.

STEP 3: FIRST PROVE

Cover and prove at room temperature for 60 to 90 minutes until doubled, or overnight in the fridge. The cold prove gives better flavour and a much easier dough to shape.

STEP 4: MAKE THE ACIDIC GEL

Warm the cider vinegar, apple juice and sliced onion together to a bare simmer, take off the heat and infuse for 15 minutes. Strain, then top up with a little more apple juice to bring the liquid back to 250 g, since the onion will have taken up some of it. Return it to the pan with the caster sugar and salt, whisk in the agar agar while the liquid is still cold, then bring to a full rolling boil and hold it there for 2 minutes. Agar will not set unless it boils properly. Pour into a shallow tray and chill until firm, about 30 minutes.

STEP 5: BLITZ THE GEL TO A FLUID GEL

Cut the set gel into cubes and blitz smooth, adding a spoonful of water if it seizes. You want it pipeable and glossy, thick enough to sit in the middle of a doughnut without leaking. Pass it through the sieve, load it into a piping bag and chill.

STEP 6: SWEAT THE ONION FOR THE CREAM

Cook the sliced onion very slowly in the unsalted butter with a pinch of salt for 20 to 25 minutes, until completely soft and sweet but with no colour. Colour here reads as caramel and pulls the whole dish sweet.

STEP 7: INFUSE THE CREAM BASE

Add the whole milk, 150 g of the double cream and the bay leaf to the onions and bring to a bare simmer. Take off the heat, cover and infuse for 20 minutes, then lift out the bay leaf and blitz. Strain through the sieve. Keep the remaining 50 g of double cream cold in the fridge, because you may need it in step 10.

STEP 8: BUILD THE CUSTARD

Whisk the egg yolks with the cornflour until smooth. Pour a third of the warm infused cream over them, whisking as you go, then return everything to the pan. Cook over a medium-low heat, whisking constantly, until it thickens to a coating custard at about 82 to 84 C. Do not let it boil.

STEP 9: ADD THE CHEESE OFF THE HEAT

Pull the pan from the heat, wait 30 seconds, then add the grated aged Irish cheddar in three additions, whisking each one in fully. Season with fine sea salt and white pepper. Cheese added to a custard still over the flame is the most likely cause of a split, which is why the pan comes off first.

STEP 10: RESCUE THE CREAM IF IT SPLITS

If the cream breaks, take it off the heat, add the reserved 50 g of cold double cream a spoonful at a time and blend hard with a stick blender until it comes back together. Blending while it is still warm is what re-emulsifies it. Kristen used exactly this save on the day and served the cream.

STEP 11: SET THE CREAM

Pass the cream through the sieve into the serving vessels, about 25 g in each, cover with cling film touching the surface, and chill for at least 2 hours until set to a soft, spoonable custard.

STEP 12: CRISP THE POTATO SKINS

Peel the potatoes in wide strips, or bake them whole and scoop out the flesh, then cut the skins into shards. Dry them thoroughly and fry at 170 C until deep gold and rigid, 2 to 3 minutes. Drain on paper and salt straight away. Make these last if you can, or keep them airtight with a silica sachet.

STEP 13: MAKE THE CHEESE AND ONION DUST

Dry the grated hard cheese in a 90 C oven until brittle, 30 to 40 minutes. Blitz it with the cheese and onion crisps and the onion powder to a fine powder. Keep it dry and airtight.

STEP 14: SHAPE AND SECOND PROVE

Knock back the dough and divide it into 12 pieces of about 30 g. Roll each one tight into a ball on an unfloured surface. Set them on squares of oiled baking paper, cover, and prove for 45 to 60 minutes until visibly puffed and slow to spring back.

STEP 15: FRY THE DOUGHNUTS

Heat the neutral oil to 170 C. Lower the doughnuts in on their paper squares, three at a time, removing the paper once they release. Fry for 90 seconds a side to deep gold. Below 165 C they come out greasy; above 180 C the centres stay raw while the outsides burn. Drain briefly, then roll the hot doughnuts in the cheese and onion dust.

STEP 16: FILL THE DOUGHNUTS

While they are still warm, pierce each doughnut at the equator with a skewer, work the hole open, and pipe in the acidic gel until you feel the weight change, about 8 to 10 g each. Fill them warm, because a cold doughnut tears.

STEP 17: ASSEMBLE AND SERVE

Sit a filled doughnut on each portion of set cheese and onion cream and top with shards of crispy potato skin. Send them out immediately. The doughnut should still carry a little warmth against the cold cream, and that contrast lasts about four minutes.