Madeleine

In a large bowl, use a hand mixer to beat the eggs and sugar on high speed for 5-8 minutes until the mixture is pale, thick, and forms a ribbon when the beaters are lifted.

Gently fold in the lemon zest and vanilla extract. Sift the flour mixture over the egg mixture in two additions, carefully folding it in with a spatula.

Take about 1/2 cup of the batter and mix it into the melted butter. Then, gently fold this butter mixture back into the main batter until just incorporated. Cover and chill the batter in the refrigerator for at least 1 hour (or overnight) to help them rise and form the characteristic hump.

Preheat the oven to 375°F (190°C). Generously butter and flour a madeleine pan. Drop a tablespoon of chilled batter into the center of each shell mold (do not spread it out).

Bake for 10-12 minutes until the edges are golden and the centers spring back when lightly touched. Invert the pan immediately onto a wire rack to release the madeleines.