Here's a recipe I developed over 15 years ago and love it.
KATIE’S OVEN ROASTED TOMATO SAUCE
(Makes about 3 cups)
5 Tbsp. extra-virgin olive oil
3 lbs. Roma or plum tomatoes, cut lengthwise in halves
Salt and freshly ground black pepper
2 cloves garlic, minced
¼ tsp. crushed red pepper flakes
¼ cup fresh basil leaves, cut into thin ribbons
Generously brush a large baking sheet with 1 tablespoon of the olive oil.
Season the cut sides of the tomatoes with salt and pepper. Place, cut side down, on the baking sheet. Brush the skins with 2 tablespoons of the olive oil. Bake in a preheated 450º until the tomato skins are lightly browned and the tomatoes are tender, 30 to 35 minutes. Cool completely. Pull the skins off the tomatoes and discard.
Meanwhile, heat the remaining 2 tablespoons of olive oil, the garlic and red pepper in a small skillet over medium heat until the garlic has softened but has not browned, about 2 minutes. Puree the tomatoes, pan juices and garlic oil in a food processor fitted with the metal blade. Stir in the basil and season to taste with salt and pepper. Process until the basil is uniformly distributed through the sauce.
The sauce can be prepared up to 3 days ahead, cooled, covered, and refrigerated or frozen for up to 2 months. It can also be canned in a water-bath. Fill clean sterilized jars, leaving ½-inch head space. Process pints for 15 minutes.
P.S. I've also used other types of tomatoes with success when I didn't have any plum tomatoes.