- 5 cups canned peeled tomatoes in their liquid
- 1 small onion, minced
- 1 stick (4 ounces) unsalted butter
- 1/2 teaspoon salt
- 3 tablespoons finely chopped fresh basil, flat-leaf parsley or mint
- Freshly ground pepper
- Drain the tomatoes in a strainer set over a bowl. Scoop out and discard any seeds from the tomatoes. Crush the tomatoes well and place them in a separate bowl; reserve their liquid for another use.
- In a large nonreactive saucepan, cook the onion in 6 tablespoons of the butter over moderately low heat until golden. Add the tomatoes and salt and simmer over moderate heat for 20 minutes.
- Just before serving, stir in the remaining 2 tablespoons butter and the basil and season with pepper.
The sauce can be tightly covered and refrigerated for up to 5 days or frozen for up to 3 months.