In a bowl, combine 200 g crushed Biscoff cookies, 2 tbsp sugar, 1/4 tsp salt, and the melted 100 g butter. Stir until the crumbs are evenly moistened.

Press the mixture into the base of a 9-inch springform pan (or an 8–9 inch tart pan), using the bottom of a glass for an even, compact crust. Chill in the refrigerator for at least 20 minutes to firm up.

Sprinkle 2 tsp gelatin powder over 3 tbsp cold water in a small bowl and let sit for 5 minutes. Gently warm the bloomed gelatin (over a double boiler or 5–10 seconds in the microwave) until fully dissolved; don’t let it boil. Set aside to cool slightly.

In a chilled bowl, whip 400 ml heavy cream to soft peaks. Refrigerate the whipped cream while you prepare the Biscoff base.

In a separate bowl, beat 100 g softened cream cheese, 250 g Biscoff spread, 50 g powdered sugar, and 1 tsp vanilla extract until smooth and glossy.

Slowly drizzle the slightly cooled dissolved gelatin into the Biscoff-cream cheese mixture while stirring constantly so it blends evenly.

Gently fold the whipped cream into the Biscoff mixture in three additions, keeping the texture airy and light.

Pour the mousse over the chilled crust and smooth the top with an offset spatula. Refrigerate for at least 4–6 hours, or overnight for the best set and clean slices.

Before serving, sprinkle 100 g crushed Biscoff cookies over the top and add chocolate shavings or a light dusting of cocoa powder for contrast.