Ingredients
Preparation
Step 1
Preheat the oven to 400°F.
Step 2
Scatter the red onion, chiles, garlic, and basil and oregano sprigs in a baking dish. Core the yellow tomatoes and place them, stem side down, on top of the onions. Sprinkle with 2 teaspoons salt, and pour the olive oil and 1 cup water over the tomatoes.
Step 3
Cook the tomatoes in the oven about 50 minutes, until they soften and blister. Remove the pan from the oven, and let cool 10 minutes. Strain the tomatoes and onions over a bowl, saving the juice. Discard the herbs and half the chiles.
Step 4
Transfer half the tomato mixture to a blender with 1/2 cup of the liquid. (You will need to purée in batches.) Process at the lowest speed until the tomatoes are puréed. Pour in more liquid, a little at a time, until the tomato confit is the consistency of heavy cream. Turn the speed up, and blend about a minute, until completely smooth. Transfer to a container, and repeat with the second half of the tomatoes. (You may not need all the liquid.) Season with 1/2 teaspoon salt and some pepper. Taste for seasoning.
Note
Step 5
The tomatoes need to fit snugly in the baking dish in one even layer. If there is too much room in the pan, the sauce will be thin and lose some of its intensity.
