130 grams unsalted butter
for the glaze
150 grams confectioner's sugar
Melt the butter in a small saucepan on medium heat until it just starts to turn golden brown. Be careful not to over heat. Set aside to cool.
Using a pastry brush, generously grease the madeleine tin with a little of the melted butter. Dust with flour and place the tins in the refrigerator to set.
Using a stand mixer, whisk the eggs, egg yolk, sugar and the salt until the batter starts to thicken, about 5 minutes.
Sift the flour and baking powder and use a spatual to fold the flour into the batter mixture.
Add the orange zest to the cooled butter, then slowly drizzle the butter into the batter until you have incorporated all of the butter in the mixture.
Cover the bowl and place in the refrigerator for at least 1 1/2 hours. Preheat the oven to 425 degrees F.
Drop the batter in the middle of each mold until about three-quarters full without spreading it. Bake for 8 to 9 minutes in the upper third of your oven. Bake until slightly brown or them feel set to the touch.
To make the glaze, stir together the confectioner's sugar and the orange juice.
Remove the madeleines from the oven and place on a cooling rack. When cool, using a pastry brush, apply the glaze on both sides. Leave on the rack until the glaze has set.