Boil the whole wheat fusilli in boiling water and drain it well.
Finely chop the onion and garlic.
Heat olive oil in a pan and sauté the garlic and onion.
Add the tuna and stir-fry together.
Add chopped tomatoes and tomato sauce, and bring to a boil.
Season with salt and pepper to taste.
Add the cooked fusilli to the sauce and mix well.
Serve on a plate and enjoy.