Line two baking sheets with parchment paper or silicone mats. Preheat your oven to 300°F (150°C).

In a mixing bowl, sift together the almond flour and powdered sugar.

In a clean bowl, begin whipping the egg whites with cream of tartar. Slowly add granulated sugar until stiff peaks form.

Fold in the vanilla extract and blue gel food coloring into the meringue.

Gently fold the sifted dry ingredients into the meringue in three parts.

Transfer the macaron batter into a piping bag fitted with a round tip and pipe 1½-inch rounds onto baking sheets.

Let the piped macarons rest at room temperature for 30-60 minutes.

Bake the macarons for 15-18 minutes, rotating halfway through.

Prepare the vanilla buttercream by beating softened butter, then adding powdered sugar, heavy cream, vanilla extract, and a pinch of salt.

Pipe a dollop of buttercream onto half the shells and top with the remaining shells, dusting with edible glitter.