Preheat oven to 350 degrees. Line an 8x8 baking pan with parchment paper.
Mix together all the frangipane ingredients in a small bowl and set aside.
In a medium sized bowl, mix together softened butter, brown sugar, vanilla bean paste, and almond extract.
Stir in both flours, baking powder, and salt.
In your 8x8 pan, layer ½ base dough, ½ frangipane, other half base dough, then rest of frangipane to top. Sprinkle on sliced almonds.
Bake 40-45 minutes until almonds are toasted and toothpick comes out mostly clean.
Let cool completely then sprinkle with flakey sea salt and dust on powdered sugar.
