Start by sifting together 1 cup of almond flour and 1 ¾ cups of powdered sugar in a mixing bowl. Set aside.

In a stand mixer, whisk 3 large egg whites with ¼ teaspoon of cream of tartar until frothy. Gradually add 1 cup of granulated sugar and whip until stiff peaks form, about 4-5 minutes.

Gently fold in the sifted almond flour and powdered sugar mixture into the meringue in two batches until you reach a thick, glossy consistency.

Divide the batter into two bowls, adding teal gel food coloring to one and folding gently until combined.

Fill a piping bag with one color of the batter and pipe 1.5-inch circles on a silicone mat. Sprinkle with colorful sprinkles and let sit for 30-45 minutes until a skin forms.

Preheat oven to 295°F (145°C). Bake for 15-16 minutes until the tops are smooth and firm, then cool completely.

Beat ½ cup of unsalted butter until creamy, then gradually add 2 cups of powdered sugar and 2 tablespoons of vanilla extract. Mix in ¼ cup each of heavy whipping cream and white cake mix until fluffy.

Pipe buttercream onto half of the cooled macaron shells and top with the remaining shells. Refrigerate for 24 hours before serving.