Makes 3 cups; serves 4

• 1 1/2 pounds medium plum tomatoes (about 7), halved lengthwise
• 5 cloves garlic, peeled
• 1 medium yellow onion, peeled and quartered
• 2 tablespoons olive oil
• 1 teaspoon kosher salt
• 3 to 4 sprigs fresh thyme
• 1/3 cup fresh basil leaves (about 2 sprigs)

Heat the oven to 400 degrees F.

Place 1 1/2 pounds halved medium plum tomatoes, 5 peeled garlic cloves, and 1 quartered yellow onion on a rimmed baking sheet. Drizzle with 2 tablespoons olive oil and sprinkle with 1 teaspoon kosher salt. Toss with your hands until the vegetables are coated in oil. Arrange into a single layer. Top with three to four fresh thyme sprigs.

Roast until the vegetables are browned in spots, 25 to 30 minutes.

Pick the thyme leaves from the stems and add to a blender or food processor; discard the stems. Transfer the vegetables and any juices on the baking sheet to the blender. Add 1/3 cup fresh basil leaves. Process until smooth.

This makes enough sauce to serve with 1 pound of cooked dried pasta.

Leftovers can be refrigerated in an airtight container for up to four days or frozen for up to three months.