Cook the Whole Wheat Spaghetti: Bring a large pot of salted water to a boil. Add the whole wheat spaghetti and cook according to the package instructions until al dente. Drain the cooked spaghetti and set it aside.
Prepare the Sauce: In a large pan, spritz some cooking spray over medium heat. Add the minced garlic and diced onion and sauté for about 2 minutes until they become fragrant and slightly translucent.
Combine Tuna, Tomatoes, and Capers: Add the drained tuna to the pan and break it into smaller pieces with a fork.Add the tomatoes and capers to the pan. Stir everything together and cook for about 3-4 minutes until the tomatoes begin to soften.
Season and Add Spice: Season the mixture with salt, pepper, and crushed chilli (adjust the spice level to your preference).Stir in the lemon zest and juice for a burst of freshness.
Combine with Spaghetti: Add the cooked whole wheat spaghetti to the skillet and toss everything together until the pasta is well coated and heated through.
Serve: Divide the spaghetti with tuna, capers, and tomatoes among serving plates. Garnish with fresh chopped parsley. Serve hot and enjoy your healthy and delicious meal!