In a small bowl sift the flour and baking powder and set aside.
Using a mixer, beat the eggs and sugar at high speed until the mixture is thick and pale.
Beat in the vanilla extract and lemon zest.
Add in about one-third of the flour over the whipped eggs and gently fold in, using a rubber spatula.
Fold in half of the remaining flour, and then fold in the rest.
Do not over mix or the batter will deflate
Fold in the melted butter, bit by bit.
If you have time, cover and refrigerate the batter for at least 3 hours or preferably overnight. If not, you can bake without keeping the batter in the fridge.
Preheat your oven to 375 degrees F (190 degrees C).
Generously grease the molds of two Madeleine pans with butter.
Refrigerate the pans until the butter hardens (about 10 minutes).
Drop a generous tablespoonful of the batter into the center of each prepared mold.
Top with a couple of blueberries.
Bake the Madeleines for about 10-15 minutes, until the edges are golden brown.
Remove the Madeleines from the mold and let it cool on a wire rack.
Recipe by Maya Kitchenette at https://mayakitchenette.com/lemon-and-blueberry-madeleines/