3-4 pounds ripe tomatoes
1 medium onion, halved and sliced
2-3 cloves of garlic, smashed and peeled
a large pinch of dried herb, crumbled (marjoram, thyme, basil or oregano) or 1 teaspoon chopped fresh
1/4 cup olive oil
1 tsp. salt
1 tsp. sugar
freshly ground black pepper
Heat the oven to 375. Slice the tomatoes in half lengthwise, then arrange them cut-side down, in one layer on a large, rimmed baking sheet (mine is 12-by 17-inches), lined with parchment paper, if you like, for easier clean-up. Arrange the onions, garlic and herbs over the top, then drizzle the whole thing evenly with olive oil and sprinkle with salt, sugar, and pepper. Bake for an 1-1 1/2 hours or until the tomatoes are browning in spots and have ful1y collapsed. Around an hour in, the tomatoes will be sitting in a flood of juice in their pans, and then this juice will reduce as they cook further.
After cooking, put everything in the blender. Salt and add more salt or sugar as needed. Allow it to cool, then freeze.