No-Bake Biscoff Millionaire’s Slice

If you’re a fan of Biscoff, this no-bake millionaire’s slice is about to become your new obsession. Imagine a crunchy Biscoff biscuit base, topped with a thick, gooey caramel layer, and finished with silky white chocolate swirled with Biscoff spread. It’s indulgent, rich, and absolutely irresistible. The best part? No oven required.

Why This Recipe Works

Traditional millionaire’s shortbread uses a buttery biscuit base, caramel, and milk chocolate topping. This twist swaps the base for spiced Biscoff biscuits, which add a caramelised crunch that pairs perfectly with the smooth caramel layer. White chocolate on top keeps things sweet and creamy, while melted Biscoff spread swirls make every slice look as good as it tastes.

Tips for Perfect Slices

• Line your tin well: Use baking parchment with an overhang so you can easily lift out the slice once it’s set.
• Low and slow caramel: Don’t rush the caramel—it needs to gently thicken without burning. Stir constantly for a smooth, “fudgey” layer.
• Sharp knife trick: For clean slices, dip your knife in hot water, wipe it dry, then cut. Repeat for each slice.
• Make ahead: This slice keeps beautifully in the fridge for up to 5 days, or can be frozen for up to a month.
• Customize it: Swap the white chocolate for milk or dark if you prefer, or add extra crushed biscuits on top for crunch.

Why You’ll Love This Recipe

This no-bake Biscoff millionaire’s slice is the ultimate treat for cookie butter lovers. It’s crunchy, creamy, gooey, and looks stunning with its marbled topping. Best of all, it’s surprisingly simple to make and doesn’t require turning on the oven. Perfect for parties, bake sales, or simply to keep in the fridge when you want a decadent sweet fix.

Once you’ve made it, don’t be surprised if it disappears faster than you expected—everyone always comes back for seconds.

Print

Biscoff Millionaire’s Slice

Course Dessert

Cuisine American

Keyword biscoff, biscoff caramel slice, caramel slice, easy dessert, millionares slice, no-bake, tray bake

Prep Time 40 minutes minutes

Cook Time 15 minutes minutes

chilling 3 hours hours

Total Time 3 hours hours 55 minutes minutes

Servings 18 bars

Calories 396kcal

Equipment

• 20cm deep square baking tray
• baking paper

Ingredients

Base

• 300 g Biscoff Lotus biscuits
• 1 tsp ground cinnamon
• 150 g unsalted butter

Caramel

• 150 g light muscovado sugar (or light brown sugar)
• 150 g butter
• 1 tin condense milk

To finish

• 250 g white chocolate
• 50 g Biscoff sprad (smooth)

Instructions

• Line up your baking tray with baking paper. Process biscuits and cinnamon in food processor until you get fine crumb. You can alternatively put the biscuits into a plastic bag and break them down with a rolling pin. Stir in melted butter and mix until evenly incorporated. Transfer into the prepared tray and press down with the back of the spoon into even layer. Chill in the fridge for about an hour.
• Prepare your caramel layer about 15 mins before the biscuit layer is ready. Over medium heat, heat butter and sugar until melted. Add condense milk, bring to boil and cook for about 10-15 minutes, stirring continuously until its pale caramel colour and thickened. It should have around 110ºC on thermometer. Once ready, pour over biscuit base and chill for about an hour in the fridge.
• For the topping, melt the white chocolate in the bowl over hot water, make sure the bowl does't touch the water. Heat Biscoff spread in microwave for 10 seconds and stir until smooth. Once chocolate is melted, pour it over the caramel layer. Drizzle Biscoff spread over white chocolate and use cocktail stick to create marble effect. Chill in the fridge until set, about an hour. Allow to soften to room temperature before cutting into bars. Use sharp warm knife (run it under hot water for few seconds) once you're ready to cut them.