Mix 250g almond flour, 80g stevia, and 1/2 tsp baking powder with 110g melted butter, then add 1 egg. Spread 2/3 of the dough onto a baking pan lined with parchment paper and bake at 180°C for 15 minutes.
In a saucepan, gently stir and heat 60g butter and 50g allulose over low heat. Add 200ml heavy cream, a pinch of salt, and a dash of vanilla extract, stirring until thickened.
Pour the caramel over the baked dough, add small pieces of the remaining dough on top, and bake again at 180°C for 10 minutes.
Let cool, then freeze for 15 minutes. Store in the freezer.