Butter-Tomato Pasta Sauce

1. 3 tablespoons butter
2. 34 tablespoons extra-virgin olive oil
3. 1 medium onion, finely chopped
4. salt and pepper
5. 2 lb (approximately 1 kg) very ripe fresh tomatoes, peeled and pureed
6. 45 fresh basil leaves
7. 1 lb (450 gr) pasta (penne, spaghetti, or 1/2 lb-250 gr fettuccine
8. noodles)
9. 1/2 cup (75 gr) parmigiano reggiano cheese, freshly grated

In a medium-size saucepan, place the butter and olive oil. Turn the heat to medium. As soon as the butter starts foaming, add the onion, salt, and pepper. Saute until the onion becomes soft and translucent. Add the tomatoes and basil leaves. Cook uncovered over medium heat for about 2025 minutes, stirring frequently. Cooking time may vary depending on the type and ripeness of the tomatoes. Cook the pasta in abundant salt water following manufacturers instructions. Taste for readiness from time to time, until al dente (firm but not too soft or overcooked). Drain and transfer to a bowl. Top with the sauce and the cheese, toss, and serve immediately.