Mix the flour with the baking powder and salt and set aside. Melt the butter and set aside. Zest the mandarin and set aside.
In a stand mixer, or by using a hand mixer, beat the eggs, vanilla, zest and sugar for 8 minutes on medium high speed.
Place a sieve over the mixture and run the flour mix through it. Then gently fold the flour into the mix.
Take a quarter of the batter and mix it with a spoon into the melted and cooled butter. Then pour the butter mix back into the batter and fold gently until it is all incorporated.
Cover and refrigerate the mix for 30 minutes. At the 15 minute mark, preheat the oven to 180C.
If you are using a metal madeleine pan, butter it. I used a silicone one, and there is no need to butter that one. Then spoon the batter into the madeleine spots and bake for 6-9 minutes depending on the size of your madeleines. We made 48 madeleines but our mold is a bit small. They are best eaten fresh!
