Sift the powdered sugar and almond flour together twice.

Beat the egg whites on medium speed until foamy and gradually add granulated sugar and cream of tartar, increasing speed to high until stiff peaks form.

Add green gel food coloring to the meringue and gently fold in the sifted almond flour and powdered sugar.

Pipe the macaron shapes on lined baking sheets.

Tap the baking sheets to release air bubbles and let sit for 30 to 60 minutes.

Preheat oven to 300°F (150°C) and bake macarons for 14-16 minutes.

Cool baked macarons on baking sheets.

Beat softened butter until fluffy, then gradually mix in powdered sugar, heavy cream, vanilla extract, and crushed snack cakes to make filling.

Pipe filling onto half of the macaron shells and sandwich with the other half.

Optional: Drizzle with melted white chocolate and sprinkle with festive decorations.