Step 1

Preheat the oven to 350°F/175°C. Grease the baking pan and sprinkle with ground almonds.

Step 2

Carefully separate the eggs. Beat the egg whites with completely fat-free, clean whisks until stiff, adding 50 grams of sugar towards the end. In a second bowl, beat the egg yolks with the remaining sugar for a few minutes until creamy.

Step 3

Stir the almonds (and lemon zest, if desired) into the egg cream. Gradually fold in the beaten egg whites carefully but gently. You should stop stirring vigorously (like with sponge dough) but fold in with a whisk or dough scraper.

Step 4

Pour the dough into the pan, smooth it out and bake for about 40-45 minutes. Test with a chopstick. The cake may still be moist.