PREPARE YOUR WORKSPACE:
Position racks in the upper and lower thirds of your oven. Preheat to 350°F (180°C / 160°C fan). Line baking sheets with silicone mats or parchment paper—this is essential as the caramel is extremely sticky.

Roughly chop the pecans into pieces about the size of sliced almonds. Chop the golden raisins to prevent them from creating overly large pockets. Combine the sliced almonds, chopped pecans, and chopped raisins in a bowl and set aside.

MAKE THE CARAMEL BASE:
In a heavy-bottomed saucepan, combine the butter, brown sugar, and golden syrup. Place over medium heat and stir constantly until the butter melts and the sugar dissolves completely.

Once dissolved, stop stirring and let the mixture come to a gentle boil. Allow it to bubble for exactly 1 minute—this develops the caramel flavor without burning. Remove from heat immediately.

Carefully stir in the heavy cream (it will bubble up vigorously) and the flaky sea salt. The mixture should be smooth and glossy.

Add the flour to the caramel, stirring until no lumps remain. Fold in the prepared nuts and raisins until evenly distributed. The mixture will be loose and sticky—this is correct.

SHAPE AND BAKE:
Working quickly while the mixture is still warm, drop level teaspoons of batter onto your prepared baking sheets, spacing them at least 3 inches (7.5cm) apart. These spread significantly during baking. You should get about 12 per standard baking sheet.

Use the back of a wet spoon or wet fingers to gently press each mound into a rough disc about 1½ inches (4cm) in diameter. Don't worry about perfection—they will spread and even out.

Bake for 10-12 minutes, rotating the sheets halfway through. The florentines are done when they are golden brown throughout (not just at the edges) and bubbling has nearly subsided. The centers should appear set, not wet.

Watch carefully in the final minutes. Underbaked florentines will be chewy rather than crisp; overbaked ones become bitter. The color should be an even caramel-gold, darker at the very edges.

Let the florentines cool on the baking sheets for 5 minutes—they are too fragile to move while hot. Once they begin to firm up, transfer to wire racks using a thin spatula. They will continue to crisp as they cool.

Once fully cooled (about 20 minutes), test one florentine by breaking it. It should snap cleanly with a satisfying crack. If it bends or feels chewy, return the batch to the oven for 2-3 more minutes.

TEMPER AND APPLY THE CHOCOLATE:
For a professional finish with proper snap and shine, temper your chocolate. Melt two-thirds of the chopped dark chocolate in a double boiler or in 30-second microwave intervals, stirring between each, until it reaches 115°F (46°C). Remove from heat and add the remaining third of chocolate, stirring constantly until it melts and the temperature drops to 88-90°F (31-32°C).

Turn each cooled florentine flat-side up (the bottom becomes the presentation side). Using an offset spatula or the back of a spoon, spread a thin, even layer of tempered dark chocolate over the flat surface, bringing it just to the edges.

Before the chocolate sets, drag a fork through the chocolate in a wavy pattern—this classic florentine decoration helps the chocolate adhere and creates visual interest.

If desired, temper the milk chocolate using the same method and drizzle thin lines across the dark chocolate base for Laura's original two-chocolate approach.

While the chocolate is still tacky, sprinkle a few flakes of sea salt over each florentine for extra salted caramel punch.

Place chocolate-side up on parchment-lined sheets. Let set at cool room temperature (68-72°F / 20-22°C) for at least 30 minutes, or refrigerate for 10 minutes if your kitchen is warm.