Melt the butter and chocolate over a double boiler.

Stir until smooth. Cool

Add the vanilla, eggs, and sugar.

Whisk until smooth.

Fold in flour and baking powder.

The batter will be thick. Cover with plastic wrap and chill for 2 hours.

Spray the madeleine pan with cooking spray. Bake in a 375 degree oven for 10 to 13 minutes.

Flip the cookies out and cool on a rack.

Serve with White Hot Fudge Sauce