Preheat oven to 350°F. Line an 8- x 8-inch baking dish with parchment paper or foil. Grease the parchment or foil.
Heat butter until hot. Add sugar, vanilla, salt, almonds, cake meal, and lemon zest. Stir just to combine. Transfer crust to lined pan and press into the pan.
Bake at 350°F until lightly browned, about 20 to 25 minutes. Set aside.
For the filling:
Decrease oven to 300°F.
Whisk together sugar, starch, eggs, zest, juice, salt, and vanilla until well combined.
Gently pour filling into baked crust. Bake the bars for 20 to 25 minutes until the center is no longer jiggly.
Cool completely before garnishing with powdered sugar.