Step 2

Melt the butter in a small pan and set it aside to cool. Warm butter would start cooking the egg white when it goes in.

Step 3

Sift the powdered sugar and flour into a bowl, add the ground almonds, and rub everything together with your fingertips until it looks even.

Step 4

In a separate bowl, whisk the egg whites only until they collapse into a loose, floppy foam. They should not hold a peak.

Step 5

Make a well in the dry ingredients, tip in the whites and the lemon zest, then trickle the cooled butter over and stir lightly into a soft batter.

Step 6

Divide the batter between the pans with a large serving spoon and drop a handful of blueberries onto each one.

Step 7

Bake for 15–20 minutes, until golden and just firm when you press the top.

Step 8

Leave them in the pans for 5 minutes, then turn out onto a wire rack. Dust with powdered sugar to serve.