Preheat your oven to 300°F (150°C) and line two baking sheets with parchment paper. Sift together the almond flour and powdered sugar.

In a separate bowl, whip room temperature egg whites until foamy, then add granulated sugar until stiff peaks form. Mix in vanilla and food coloring. Fold in the dry ingredients.

Transfer the batter into a piping bag and pipe small rounds onto the prepared sheets. Let them rest until the surface is dry.

Bake for 15-20 minutes until firm and have developed a nice foot. Let them cool completely.

Beat the softened unsalted butter until smooth, then add the powdered sugar and raspberry puree with salt, beating until fluffy.

To assemble, pipe buttercream onto one macaron shell and cap with another. Stack several together as desired.

Refrigerate the assembled stack for at least 30 minutes before serving.