Hearty Swiss Roulade

Peel carrots and finely grate. Put half the grated carrots in a small bowl, cover with plastic wrap and set aside.

Separate eggs. Beat egg whites in a tall vessel until stiff with the whisk attachment of a hand mixer. Reserve in refrigerator. 

Put the margarine in a mixing bowl and beat until fluffy with the mixer. Gradually beat in the egg yolks. 

Combine flour, cornstarch, baking powder, salt and pepper in a bowl and add to the yolk mixture in 2 batches, beating to combine.

Add the remaining grated carrots and the egg whites and fold into batter with a rubber spatula.

Line a baking sheet with parchment paper. Spread the batter on top and bake on second rack from the bottom of preheated oven at 200°C (fan 180°C, gas mark 3) (approximately 400°F/convection 350°F) until golden brown and springy to the touch, 15-20 minutes.

Invert the sponge cake onto a kitchen towel and let cool for a few minutes. Peel off the parchment paper. 

Starting from a long side, roll up the cake loosely, incorporating the towel as you go. Allow to cool completely, about 30 minutes.

Meanwhile, cut the cress from the roots with kitchen shears and set aside half of cress. Stir the quark in a bowl until creamy and season with salt and pepper. Fold in the cress and the reserved (refrigerated) grated carrots.