Preheat the oven grill. Cook pasta in plenty of salted water according to package instructions until firm to the bite. Drain.
Rinse and drain the lenses. Peel, wash and grate carrots. Peel and crush garlic. Melt butter in a pot and fry garlic for a few minutes. Add lentils, 1⁄2 l water, carrots and 1 teaspoon paprika, bring to the boil and cook for about 20 minutes with the lid on very softly. If there is still plenty of water, continue cooking for a few minutes without the lid on.
Fold in mustard, 1 teaspoon salt, vinegar, cottage cheese or ricotta, 1⁄2 teaspoon black and 1 large pinch of white pepper and, if used, 1 large pinch of freshly grated nutmeg. Blend until smooth and season to taste. The sauce should be smooth and creamy. If it looks too dry, add some water.
Fold in the pasta. Grate cheese. Pour the pasta mixture into an ovenproof dish (approx. 16 x 20 cm) and smooth it down with the back of a spoon. Sprinkle with sunflower seeds, cheese and, if used, sesame seeds. Bake under the grill for about 5 minutes.
In the meantime clean, wash and slice the zucchini. Fry them in a ceramic-coated or cast-iron pan without fat on both sides until they are soft and browned. In a serving dish, drizzle with olive oil. Season lightly. Wash the basil, remove the leaves and pluck smaller ones, garnish the courgette with it.