Separate eggs. Beat egg whites until stiff. Salt it a little. Stir in the egg yolk. Sift flour over it and fold in carefully. Spread the sponge mixture on 1/4 of a baking tray covered with baking paper as thick as a finger.
Sprinkle with peas. Bake in the preheated oven (electric oven: 200 °C/ gas: level 3) for about 12 minutes. Before serving, cut into rhombs and add to the hot broth.