01 - Line two baking sheets with parchment paper or silicone mats. Fit a pastry bag with a 0.5-inch round tip.
02 - Sift almond flour and powdered sugar together into a bowl. Set aside.
03 - In a clean dry bowl, whisk egg whites and cream of tartar until soft peaks form. Gradually add granulated sugar while whisking until stiff glossy peaks form.
04 - Gently fold almond flour mixture into meringue in three additions. Tint one-third of batter yellow with gel coloring for yolk effect. Mix until batter flows in thick ribbons (macaronage stage).
05 - Transfer batter to pastry bag. Pipe 32 rounds about 1.5 inches wide onto prepared sheets. Tap trays firmly on counter to release air bubbles.
06 - Let shells rest at room temperature for 30-60 minutes until surfaces form dry skin and no longer feel tacky to touch.
07 - Preheat oven to 300°F. Bake for 13-15 minutes, rotating pans halfway through. Shells are done when they easily lift from baking surface. Cool completely.
08 - Heat heavy cream until just simmering. Pour over chopped milk chocolate, let sit 2 minutes. Stir until smooth. Add golden syrup and butter, mix until glossy. Divide one-quarter of filling and tint yellow for yolk center. Chill until thickened.
09 - Pipe ring of chocolate filling on one shell. Place dollop of yellow filling in center for yolk effect. Top with another shell and press gently. Repeat with remaining shells.
10 - Store assembled macarons in airtight container overnight at room temperature for flavors to mature and texture to develop.