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.
03 - Whisk egg whites and cream of tartar in a clean, dry bowl until soft peaks form. Gradually add granulated sugar, continuing to whisk 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 about 1.5 inches in diameter onto prepared sheets. Tap trays firmly to release air bubbles. Let shells rest at room temperature 30-60 minutes until surfaces are dry to touch.
06 - Preheat oven to 300°F. Bake 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 sit 2 minutes. Stir until smooth. Add golden syrup and butter, mixing until glossy and combined.
08 - Reserve one-quarter of ganache and tint with yellow gel coloring for the egg yolk effect. Chill both fillings until thickened to piping consistency.
09 - Pipe a ring of chocolate filling onto one shell. Place a small dollop of yellow filling in the center. Gently sandwich with another shell. Repeat with remaining shells.
10 - Store assembled macarons in an airtight container overnight at room temperature to allow flavors to mature. Refrigerate up to 5 days.