A week before

1. Mix in a bowl the almond flour with the granulated sugar. Add the lemon zest and 2-3 tablespoons water. Knead until you have a firm paste. Not too wet and not too dry.
2. Turn it into a ball and wrap the ball in clingfilm. Put it in the fridge to rest for a few days (a week is best).

Baking day

1. Mix in a bowl the gluten-free flour, dark brown sugar, pumpkin spice, salt and baking powder together. Add the cold butter and the milk and knead into a supple dough. If the dough remains too crumbly, you can add some milk. If it is too wet, you can add some extra flour.
2. Roll the dough into a ball and cover with clingfilm. Leave to rest in the fridge for at least an hour (or overnight).
3. Pre-heat the oven to 180 degrees Celcius (350 degrees Fahrenheit). Grease a rectangular baking tin and cover with baking parchment.
4. Roll the dough into two rectangular pieces. The one piece slightly bigger than the other. If the dough is difficult to roll, you can also divide pieces of dough over the baking tin and press them with your fingers into a flat piece. Put the largest piece of dough into the baking tin and also press some dough into the sides of the tin so standing edges are formed.
5. Add an egg yolk to the ball of almond paste and knead it into a supple mixture. Divide the almond paste over the layer of dough in the baking tin.
6. Put the second layer of dough on top of the almond paste and press the sides together so the almond paste is covered by the dough on all sides.
7. Beat an egg and brush it on top of the dough. Decorate the dough with some almond halves.
8. Bake the stuffed speculaas in the oven for 30-40 minutes.