Cook the lasagne sheets in boiling salted water for about 5 minutes, drain. Peel and finely dice onions. Peel carrots and cut into fine strips. Heat 2 tablespoons of oil in a pan.
Fry the minced meat in it until crumbly, season with salt and pepper. Add onion and carrots, fry briefly. Stir in tomato paste and sweat it. Season with salt, pepper and thyme. Melt the fat and sweat the flour in it.
Deglaze with milk and vegetable stock, simmer for about 5 minutes. Season to taste with salt and pepper. Add deep-frozen herbs. Spread the minced meat mixture on one narrow side of each lasagne sheet and roll up.
Place rolls side by side in an ovenproof dish, pour sauce over them and sprinkle with cheese. Bake in a preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for 10-15 minutes. Clean, wash and drain the salad and pluck into bite-sized pieces.
Wash and clean the tomato and cut it into pieces. Season lemon juice with salt, pepper and sugar, add 2 tablespoons of oil. Mix the lettuce and tomatoes carefully with the vinaigrette. Garnish pasta rolls with thyme.
Serve with the salad.