Prepare the batter:

• In a mixing bowl, whisk together eggs and sugar until pale and slightly thickened (about 3–5 minutes).
• Stir in vanilla extract, heavy cream, and lemon zest if using.

Combine dry ingredients:

• In another bowl, whisk together flour, baking powder, and salt.
• Gradually fold the dry ingredients into the wet mixture using a spatula.

Add the butter:

Slowly drizzle in the melted butter, folding gently until fully incorporated. Be careful not to overmix.

Chill the batter:

Cover the bowl and refrigerate for at least 30 minutes (or up to 2 hours). This helps create the classic Madeleine “hump” during baking.

Prepare the pan:

• Preheat oven to 375°F (190°C).

• Grease a Madeleine pan with butter and lightly dust with flour, tapping off the excess.

Bake the madeleines:

• Spoon about 1 tablespoon of batter into each shell mold. No need to spread it out—the heat will do that.
• Bake for 10–12 minutes, until the edges are golden brown and the centers spring back when lightly touched.

Cool & serve:

Remove from the pan and cool on a wire rack. Dust with powdered sugar before serving.