Prep Macaron Shells: Line baking sheets with silicone mats and preheat oven to 300°F.

Combine Dry Ingredients: Sift together almond flour and confectioner’s sugar.

Whip Egg Whites: Beat egg whites with a hand mixer until foamy, then gradually add sugar and cream of tartar until stiff peaks form.

Fold Mixtures: Fold dry ingredients into whipped egg whites until smooth.

Pipe Shells: Pipe rounds onto silicone mats and let dry until a skin forms.

Bake: Bake for about 18 minutes, rotating halfway through.

Make Buttercream: Cream salted butter and cookie butter together, then add powdered sugar and heavy cream.

Assemble Macarons: Pipe filling onto one macaron shell, sprinkle crushed cookies, and sandwich with another shell.