Adapted from Essentials of Classic Italian Cooking by Marcella Hazan
- 5 Tablespoons unsalted butter
- 1 medium onion, peeled and cut in half
- 2 28-ounce cans crushed tomatoes
- 2 teaspoons salt
- In a sauce pot, melt the butter over medium heat until it’s no longer foaming.
- Add in the onion halves and stir them around in the butter until they take on a light golden color and the butter starts to brown lightly.
- Add in the tomatoes and the salt and stir to combine. Note: Do not be concerned if you see some of the butter separating and floating on top of the sauce. It will eventually blend into the sauce as you keep stirring.
- Cover the pot partially and reduce the heat to medium-low.
- Cook the sauce for 45 minutes to 1 hour, stirring occasionally.
- Towards the end of cooking, taste the sauce for salt and adjust if necessary.
- Remove the onion pieces before using the sauce.
- Storage: Cool the sauce to room temperature before transferring to freezer-safe containers. Freeze for up to 3 months.