Soften the lentils in the vegetable soup with garlic.
Peel the tomatoes, cut into quarters, remove the seeds and pre-cook in the oven at 150 °C for 10 minutes. Cut the potatoes into slices. Cut zucchini and melanzane lengthwise into narrow slices and roast briefly on both sides in a frying pan with olive oil. Season zucchini, tomatoes, potato and melanzane slices each lightly with salt and season with pepper and layer in a greased gratin dish. Sprinkle with parmesan and gratinate in a 200 °C oven.
Add whipped cream to the cooked lentils form and season strongly with salt and freshly ground pepper.
Serve the gratin, pour on the lentil sauce and sprinkle with parsley.
Tip: Zucchini is a type of squash and therefore low in calories, rich in vitamins and easy to digest – just the thing for a light meal!