1. Weigh and prepare all ingredients accurately. Line baking sheets with parchment or silicone mats and fit a piping bag with a round tip.

2. Sift together almond flour and powdered sugar. If needed, pulse in a food processor for a fine consistency and sift again.

3. Whip egg whites until foamy, then add cream of tartar. Gradually add granulated sugar while whipping to stiff, glossy peaks. Fold in lemon zest and a drop of yellow gel coloring.

4. Fold the dry ingredients into the meringue in thirds. Mix gently until the batter flows like lava and forms ribbons.

5. Pipe 1.5-inch rounds onto baking sheets. Tap trays to remove bubbles and rest until tops are dry to the touch (30–60 minutes).

6. Bake at 300°F (150°C) for 15–18 minutes until risen with feet. Allow to cool completely.

7. Make buttercream by beating butter until fluffy. Add powdered sugar, lemon juice, and lemon zest, beating until creamy.

8. Pair macaron shells by size. Pipe buttercream onto one shell and gently sandwich with another.

9. For best flavor, refrigerate assembled macarons for 24 hours, then bring to room temperature before serving.