Per original recipe, all ingredients should be brought to room temperature before mixing so that the melted butter does not congeal in the batter before the ingredients have blended together.

Combine flour, cocoa, and sugar in a mixing bowl and add three quarters of the eggs. Beat vigorously with a wooden spoon to blend into a heavy cream – if very stiff, add a little bit of the remaining egg, one droplet at a time. Set aside for 10 minutes. Meanwhile, bring all of the butter to a boil until it begins to brown very lightly. Remove 1 ½ tablespoons of the butter and combine with and tablespoon of flour in a small bowl and set aside.

Set the pan with butter in it into a larger vessel that will fit it that has been filled with cool water. Beat the remaining bit of egg (if any, I put all of my eggs in at the beginning) into the batter and stir in the cool butter. Stir in the salt and rose water (or vanilla if using).

Cover the batter, and set aside in the refrigerator for at least one hour. Meanwhile, use a rubber brush to paint the madeleine cups with a light coating of the browned butter and flour mixture, brushing away any pools that form in the bottom. Set aside or refrigerate if the kitchen is warm.

Preheat the oven to 375°. Using a spoon and rubber spatula, drop a rounded tablespoonful of batter into each Madeleine cup. Do not spread the batter to fill the mold. More is not better here. Repeat with remaining batter and mold. You may have a little batter left over. Either make the 2-3 extras or throw out the leftover batter.

Set pans on the middle rack and bake for about 15 minutes. The batter will spread on its own to fill the cups and a hump will gradually form in the middle. Unmold onto a rack, humped side up.