- Preheat oven to 170 degrees. Grease the inside of the friand tray or muffin pan well with melted butter and set aside.
- In a large mixing bowl, sift the icing sugar and flour together, and then add the almond flour. In a separate large mixing bowl, whisk the egg whites briefly until just combined, no longer than a count of ten.
- Add the melted (and cooled) butter and vanilla to the egg whites and mix for a few more seconds. Add the flour mixture and beat for about a minute, until well mixed.
- Fill each hole until about two-thirds full. Place two or three berries on top of each friand and bake until the tops are a light, golden brown. Insert a toothpick into the center to check. This is approximately 20 to 25 minutes for oval friands and 15-17 minutes for mini-muffin size. Oven temperatures can vary so keep an eye on them as they bake.
- Cool for five minutes. Use a spatula or butter knife to loosen the cakes from the pan before gently turning them out. Dust with powdered sugar and enjoy.
Note: Batter can be made up to two days in advance and refrigerated until ready to use.
Store friands in the refrigerator in an airtight container for 3 to 4 days, and bring to room temperature or heat before serving. To freeze, wrap friands individually in plastic and freeze for up to three months.