For the meatballs soak rolls in water. Peel and chop the onions. Knead minced meat, egg, squeezed out roll, salt, pepper, paprika, mustard and 1/3 of the onions well. Form small meatballs out of the minced mass with wet hands. Put them in a cold place. Clean, wash and chop the bell peppers.
Peel garlic and chop finely. Pour beans into a sieve, rinse with water and drain well. Wash the chilli pepper and cut into rings. Heat the oil in a large pan and fry the meatballs for about 6 minutes at medium heat, turning them several times. Remove from the pan and put aside. Add the rest of the onions, garlic and paprika to the frying fat and fry on all sides. Add chilli and season with salt, pepper, sugar and paprika. Add tomato paste, sweat briefly and deglaze with tomatoes. Add beans, bring to the boil and season again with salt, pepper, sugar and paprika. Add meatballs. Put everything into an ovenproof casserole dish, spread chips on top and sprinkle with cheese.
Add the rest of the onions, garlic and paprika to the frying fat and fry on all sides. Add chilli and season with salt, pepper, sugar and paprika. Add tomato paste, sweat briefly and deglaze with tomatoes. Add beans, bring to the boil and season again with salt, pepper, sugar and paprika. Add meatballs. Put everything into an ovenproof casserole dish, spread chips on top and sprinkle with cheese. Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for 20-25 minutes. Remove from the oven and garnish with mint and lemon slice