1 small yellow onion, chopped
2 garlic cloves, minced
½ teaspoon crushed red pepper flakes
2 tablespoons tomato paste
1 teaspoon fresh thyme leaves
2 (28-ounce) cans crushed tomatoes
Sea salt and freshly ground black pepper to taste
3 cups vegetable or chicken stock
½ cup heavy cream (or more to taste)
In a large pot over medium heat, heat oil. Add onion and cook until soft, 6 minutes. Add garlic, red pepper flakes, and tomato paste and cook until garlic is fragrant and tomato paste has darkened, 2 to 3 minutes more.
Add thyme and both cans crushed tomatoes. Add vegetable or chicken stock and bring up to a simmer. Cook for 10 minutes.
Blend with immersion blender or transfer to a blender in batches and blend until smooth. Add in the heavy cream and reheat the soup. Ladle into bowls and serve immediately.
Serve with grilled cheese sandwiches.