01 - Line two baking sheets with parchment paper or silicone mats. Fit a pastry bag with a 1/2-inch round tip.
02 - Sift almond flour and powdered sugar together into a bowl. Set aside for later use.
03 - Whisk egg whites and cream of tartar in a clean, dry bowl 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. Optionally tint one-third of batter yellow for yolk effect. Mix until batter flows in thick ribbons (macaronage stage).
05 - Transfer batter to pastry bag. Pipe 32 rounds, approximately 1.5 inches each, onto prepared sheets. Tap trays firmly to release air bubbles. Let shells rest at room temperature for 30-60 minutes until surfaces are dry to touch.
06 - Preheat oven to 300°F. Bake shells for 13-15 minutes, rotating trays halfway through. Shells are done when they easily lift off the mat. Cool completely before filling.
07 - Heat heavy cream until just simmering. Pour over milk chocolate and let stand for 2 minutes. Stir until smooth. Add golden syrup and butter, mixing until glossy and well combined.
08 - Divide one-quarter of the filling and tint with yellow gel coloring to create the egg yolk effect. Chill both chocolate and yellow fillings until thickened to pipeable consistency.
09 - Pipe a ring of chocolate filling onto one shell, then place a small dollop of yellow filling in the center. Gently press another shell on top to create a sandwich. Repeat with remaining shells and filling.
10 - Place assembled macarons in an airtight container. Refrigerate overnight to allow flavors to mature and textures to develop properly.