Wash basil and shake dry, pluck leaves and chop coarsely. Approx. 3⁄4 Puree basil, vinegar and 3 tbsp. oil. Season to taste with salt, pepper and sugar. Stir in the rest of the basil. Wash and slice the tomatoes.
Peel onion and cut into rings. Mix both with the dressing.
Roast pumpkin seeds in a pan without fat, remove. Heat 3 tablespoons of oil in the pan. Fry cheese in it in portions on each side for about 2 minutes. Halve diagonally, arrange on tomato salad and sprinkle with pumpkin seeds.