Heat the olive oil in a medium saucepan. Once hot, add the onion, celery, carrots and garlic. Sauté until caramelized.

Add the remaining ingredients except for the fresh basil. Cover and bring to a boil. Reduce heat to a simmer and cook for 45 minutes, stirring occasionally.

Once finished cooking, transfer the sauce to the blender and blend until smooth.

Add the fresh basil leaves to the sauce in the blender. Pulse until basil is well incorporated. Enjoy!