From the minced meat, form balls. Add salt and pepper. Peel and dice the zucchini. Also cut the peeled tomatoes into cubes. Peel and slice the onion. In a sauté pan, cook all the ingredients for 30 minutes with a little olive oil. Stir regularly.
Meanwhile, boil a large pot of salted water. When the water is boiling, add the penne in the pot and cook pasta to al dente according to the instructions on the package. When cooking is complete, drain the penne.
In a dish, mix the penne and the meatballs and stir in the sauce. Season with salt and pepper before serving hot.