This healthy pasta dish is only 500 calories per serving.
Preheat the oven to 450˚F.2.
In the work bowl of a food processor, combine the onion, carrot, celery, parsley, and garlic and process to make a smooth paste. Scrape half of the vegetable paste into a large bowl and set the rest aside in a small bowl.3.
Line a sheet pan with parchment paper. To the large bowl, add the turkey, egg, ¼ cup of the grated Grana Padano, and the bread crumbs. Season with 1 teaspoon salt. Mix with your hands until just combined. (If you like, you can fry a small patty to taste for seasoning.) Form into 18 meatballs and put on the lined sheet pan. Bake until the meatballs are firm (but they don’t have to be cooked through), about 12 minutes.4.
Meanwhile, bring a large pot of salted water to a boil for pasta. In a medium Dutch oven over medium-high heat, heat the olive oil. When the oil is hot, add the remaining vegetable paste and cook, stirring, until it dries out and begins to stick to the bottom of the pan (turn the heat down if it begins to burn toward the end). Add the tomatoes and 3 cups pasta water. Bring to a simmer and add the oregano. Season with salt and red pepper flakes. Add the meatballs to the sauce. Simmer until the meatballs are cooked through and the sauce is thick and flavorful, about 30 minutes.5.
Add the spaghetti to the boiling water. When the pasta is almost al dente, remove the meatballs from the sauce to a warm bowl and add the basil to the sauce. When the pasta is al dente, remove with tongs and add directly to the sauce, reserving the pasta water. Toss to coat the pasta with the sauce, adding a splash of pasta water if the pasta seems dry. Remove the pot from the heat, sprinkle with the remaining grated Grano Padano, and serve in warm pasta bowls, with meatballs on top.