Place the halved tomatoes cut side down on a lightly oiled cookie sheet. Turn the oven to the broil setting and place the trays into the oven. Drizzle the tops of the tomatoes with a bit more olive oil and brush to coat evenly.

Broil until skins are charred with a lot of cracks and blackened tops, about 15-20 minutes.

Drain the excess water from each tray and add the garlic pieces onto trays evenly.

Broil for another 5-10 minutes, or until the garlic has just begun to brown.

While the tomatoes are broiling, add some more olive oil into a large sauce pot. Add the onion and celery and cook until soft, about 5-7 minutes.

Remove the tomatoes from the oven and let cool for a few minutes.

Once cooled, pinch off the skins from the tomatoes. Since they tend to balloon upward, they should come off easily.

Pour the onion and celery mixture into a food processor along with a portion of the roasted tomatoes. Blend until pureed and the texture is smooth. Pour the pureed mixture back into the sauce pot.

Working in batches, blend the rest of the roasted tomatoes and garlic in the food processor until smooth. Pour each portion back into the pot.

Once all incorporated, turn up the heat to medium high and add the tomato paste, oregano, red wine vinegar, red pepper flakes, sea salt, black pepper and chicken stock (if using). Taste and adjust seasonings if necessary.

Turn down the heat and cook on low simmer for about an hour. During the last 30 minutes of cooking, stir in the fresh parsley and basil.