In a small saucepan over low heat, melt the butter and dark chocolate together until smooth. Stir gently and set aside.

In a mixing bowl, whisk the eggs and sugar until the mixture becomes smooth and slightly pale.

Place the bowl over a saucepan with simmering water (double boiler method). Whisk continuously for 2-3 minutes, until the sugar dissolves.

In a separate bowl, whisk together the flour, almond flour, cocoa powder, and baking powder.

Add the dry ingredients to the egg mixture and whisk until just combined.

Gradually add the melted butter and chocolate mixture in three additions, whisking gently each time until smooth.

Cover the batter and refrigerate for 3 hours.

Brush the madeleine pan with melted butter using a pastry brush.

Transfer the chilled batter into a piping bag and pipe about 1 tablespoon (23-25 g) of batter into each mold.

Bake in a preheated oven at 350°F (175°C) for 14-15 minutes, or until the madeleines are set.

Remove from the pan and the madeleines cool completely on a wire rack.

Temper dark, milk, or white chocolate.

Tip: If using white chocolate, you can color it with food coloring if desired.

Pour a small amount of tempered chocolate into each madeleine mold.

Gently tap the pan to spread the chocolate evenly and remove air bubbles.

Place each madeleine on top of the chocolate layer and press lightly.

Tip: Do not press too hard or the chocolate may spill out.

Refrigerate for 2-3 hours until the chocolate sets completely.

Decorate with edible gold leaf if desired.