Gather all ingredients before starting recipe.
Beat butter, sugar, zest until light and fluffy, about 3 minutes. Add yolk and vanilla and beat until combined.
Meanwhile, whisk together all purpose flour, almond flour and salt.
Add the flour mixture to the egg mixture and beat until just combined.
Divide the dough in half, pat into a disk, wrap in plastic wrap and put in the fridge until firm, about an hour.