Preheat your oven to 375°F (190°C) and grease your financier molds to prevent sticking.

In a saucepan, melt the unsalted butter over medium heat, swirling occasionally, until it turns a light brown and smells nutty—this is browned butter and adds a rich depth to your cakes.

In a mixing bowl, combine almond flour, all-purpose flour, powdered sugar, and salt; whisk until smooth.

Add in the egg whites and the browned butter, mixing well until you achieve a smooth batter. It’s important not to overmix; just combine until you see no dry flour.

Pour the batter into the financiers molds, filling them about three-quarters full, and add any chocolate pieces or berries on top if desired.

Bake for 15-20 minutes or until the edges are golden and a toothpick inserted into the center comes out clean.

Allow them to cool in the molds for a few minutes before transferring them to wire racks to cool completely.