Preheat oven (electric cooker: 225 °C/circulating air: 200 °C/gas: level 4). Rinse beans and drain well. Peel and coarsely dice onions. Cut chorizo into slices.
Heat the oil in a pan. Sauté the chorizo and onions well. Add peas, beans and tomatoes and steam briefly. Season to taste with salt, pepper and a little sugar.
Place the tortelloni and chorizo-vegetable mixture in a greased casserole dish. Sprinkle with cheese. Bake in a hot oven for 15-20 minutes.