Roasting at a high temperature gives tomatoes a rich, slightly smoky flavor, and onions and garlic become sweet as they caramelize. For those that have a fear of canning, this is a no-fail tomato sauce that can be popped into the freezer or canned, depending on your time and preference.
The sauce can be refrigerated for three to five days, or it can be frozen in a tightly wrapped plastic bag for several months. The sauce can also be placed in sterilized Mason jars and processed (20 minutes in a boiling water bath should do it); it will keep for up to 10 months.
Toss the sauce with pasta, or serve it over grilled chicken or fish, or in any dish that calls for regular tomato sauce. You can cut the recipe in half or make a huge batch, all depending on how many tomatoes you have. Feel free to add pitted olives, drained capers, chopped sweet or hot peppers, anchovies, or any other fresh herbs you have in the garden.
 
About 8 pounds ripe tomatoes, any variety, cored and quartered
10 medium onions, peeled and quartered
10 garlic cloves, peeled and left whole
5 garlic cloves, finely chopped
1 cup chopped fresh herbs (rosemary, basil, thyme, oregano, parsley, and/or chives)
About ¼ cup olive oil
½ teaspoon salt, or to taste
Generous grinding of black pepper
A few tablespoons sugar (optional)
Makes about 10 cups.
Preheat the oven to 450 degrees.
In a large roasting pan, gently toss together the tomatoes, onions, whole and chopped garlic, herbs, olive oil, salt, and pepper. Roast for 25 minutes. Gently stir the vegetables. Roast for another 25 minutes and gently toss. Add any of the optional ingredients listed above and roast for another 45 minutes, or until the tomatoes are softened and somewhat broken down into a sauce, with a golden brown crust on top. Remove and taste for seasoning. If the sauce tastes bitter, add a few tablespoons of the sugar.
Let cool and place in clean, sterile jars or tightly sealed plastic bags, and refrigerate, freeze, or can. Makes about 10 cups.