Crumble:

1. In a medium bowl put the flour with the brown sugar, almond meal, ground cinnamon, and sea salt and mix.
2. Add the chopped, cold butter and crumble it between your fingers, then gather the dough until it has a compact texture.
3. Crumble the dough into very small balls, cover with plastic wrap, and place in the fridge.

Pie crust:

1. Place the flour, powdered sugar, and pinch of salt in a bowl and mix.
2. Then add the cold butter pieces and crumble with your fingertips until you have a sandy texture.
3. Then add the cold water and gather the dough until you have a homogeneous ball of dough.
4. Cover with plastic wrap and place in the fridge for 20 minutes.
5. Roll out the dough between 2 sheets of parchment paper or on a floured work surface to a thickness of 3-4 mm.
6. Grease a 9-inch/22-24 cm pie plate with butter and line it with the pastry disk.
7. Place the pie pan in the fridge or freezer while preparing the filling.

Apple Filling:

1. In a large bowl, place the apple slices with all the other ingredients, brown sugar, vanilla, lemon juice, cinnamon, and flour.
2. Mix with a tablespoon until all ingredients are well blended together.

Baking:

1. Fill the pie pan with the apple filling and spoon the apples to fill in any voids.
2. Pour the crumble over the top until it completely covers the apples.
3. Bake in the oven on medium-high for 55 minutes to 1 hour.
4. Remove the pie from the oven and let it cool completely to room temperature.
5. Serve warm or cold with a little vanilla ice cream or whipped cream.