To a sheet pan, add roughly chopped tomatoes, onion, garlic, olive oil, balsamic vinegar, Italian seasoning, salt and pepper. Gently toss to combine all ingredients, then roast for 35-40 minutes.
2 pounds tomatoes, 1 medium onion, 6 cloves garlic, 1/4 cup extra virgin olive oil, 1 tablespoon balsamic vinegar, 1 tablespoon Italian seasoning, 1 teaspoon kosher salt, 1/2 teaspoon black pepper
Remove pan from oven and let cool at least 5-10 minutes. Carefully transfer the tomato mixture to a blender and add fresh basil. Blend on high for 1 minute, or until sauce is pureed.
1/4 cup fresh basil
Taste and adjust salt and pepper to your taste, if desired. Serve immediately, or store in an airtight container in the fridge. Enjoy!