Preparation

• If you have a food mill, quarter tomatoes. If not, peel, seed and chop them.
• To make tomato sauce, heat 1 tablespoon olive oil in a large, heavy skillet over medium heat and add onion. Cook, stirring often, until tender, about 5 minutes.
• Add garlic. Cook, stirring, until fragrant, 30 seconds to a minute, and add tomatoes, salt, pepper, sugar and basil sprigs. Increase heat to medium-high. When tomatoes are bubbling briskly, stir and reduce heat to medium. Cook, stirring often, until tomatoes have cooked down and are beginning to stick to pan, 15 to 25 minutes, depending on consistency. Remove basil sprigs; taste and adjust seasoning.
• Heat oven to 450 degrees. Line 2 sheet pans with parchment. Trim ends off zucchini and cut in half crosswise, then into lengthwise slices, about ¼ to ⅓ inch thick. Season on both sides with salt and pepper and toss with 2 tablespoons olive oil. Arrange zucchini slices on baking sheets in one layer and sprinkle with red pepper flakes. Roast for 12 minutes, until lightly browned and easily pierced with a knife. Remove from oven and reduce heat to 375 degrees.