Preheat the oven to 400°F.

Wash and core the tomatoes and slice them in half and place them on a baking sheet or in an oven safe dish. Peel and quarter the onion and add to the dish. Add cloves of garlic to the dish. Drizzle everything with olive oil and sprinkle with minced garlic salt and pepper.

Roast the tomatoes in the oven for 30 minutes or until they are soft.

Transfer everything to a blender or food processor and blend until smooth.

Using a fine mesh strainer, strain the soup removing any large chunks, skins or seeds. Add the soup to a large pot, add a pinch of chili flakes, Italian seasoning, and salt and pepper to taste. Bring the mixture to a simmer.