Prepare the Macaron Shells – Sift together the almond flour and powdered sugar. Whip egg whites until foamy, then gradually add granulated sugar, continuing to whip until stiff peaks form. Gently fold in the almond flour mixture and yellow food coloring. Pipe circles onto a parchment-lined baking sheet and let them rest for 30-40 minutes.
Bake the Macarons – Preheat oven to 300°F (150°C) and bake for 12-15 minutes until they form smooth, shiny tops with signature "feet." Let them cool completely.
Make the Marshmallow Fluff – In a saucepan, heat granulated sugar, glucose syrup, and water to 240°F (115°C). In a mixing bowl, whip egg whites and cream of tartar until soft peaks form. Slowly drizzle in the hot sugar syrup while whipping, then add vanilla extract and continue mixing until thick and glossy.
Assemble the Macarons – Pipe a generous amount of marshmallow fluff onto one macaron shell and gently sandwich it with another.
Let Them Rest – Refrigerate the macarons for 24 hours before serving to allow flavors to meld and achieve the perfect chewy texture.