So I sifted the flour and added it in gradually, folding along the way. Add the butter in a few table spoons at a time or it will sink to the bottom, dead-center in some weird pocket. To eliminate the air bubbles, I tapped the pan on the side of the counter a few times.
Note: for butter to cool back to room temperature- you need about an hour! So do that first thing or you'll find yourself begging the eggs to stay fluffy.
Best served immediately. They get harder in 2-3 days but can be treated like biscottis.
1 1/2 sticks unsalted butter (6 ounces)
2 tablespoons softened unsalted butter (for greasing pan)
4 large eggs
a pinch fine-grain sea salt
2/3 cups sugar
zest of one large lemon
1 teaspoon vanilla extract
3/4 cups unbleached all-purpose flour
powdered sugar
Preheat oven to 350 degrees. Makes 2 -3 dozen regular Madeleines.
Do ahead: melt the 1 1/2 sticks of butter in a small pot over medium heat until it's brown and gives off a deliciously nutty aroma, roughly 20 minutes. Strain (using a paper towel over a mesh strainer) - you want to leave the solids behind. Cool the butter to room temperature.
To grease the pan, use some non-stick spray with flour in it or the good ol butter/flour treatment. Get in those ridges! A cute cheat is to use the paper towel you used as a strainer because it's already soaked in butter.
Put the eggs with the salt in the bowl of an electric mixer with a whisk attachment. Whip on high speed until thick - you are looking for the eggs to roughly double or triple in volume - approximately 3 minutes. Continuing to mix on high speed, slowly add the sugar in a steady stream. Whip for 2 minutes or until mixture is thick and ribbony. Now with a spatula fold in the lemon zest and vanilla (just until mixed).
Sift the flour. Sprinkle the half of the flour on top of the egg batter, and gently fold in. Add the second half and repeat. Now fold in the butter mixture, a few tablespoons at a time. Only stir enough to bring everything together.
Spoon the batter into the molds, filling each mold 2/3 -3/4 full.