In a large spot, drizzle the bottom with olive oil and sauté the onion, celery, carrot, garlic, Italian seasoning, bay leaf, salt, and pepper for about 5 – 7 minutes.
Add the basil, stir for a minute then add the can of crushed tomatoes and tomato sauce. Stir everything together thoroughly and let simmer uncovered for 45 minutes to an hour or until it’s thickened. Stir every so often.
Remove the bay leaf from the sauce and add more salt to taste.
If you like a more smooth texture to the marinara, you can cool it and pour the sauce into a blender or food processor to your desired texture. Make a day ahead for better flavor.