Preheat your oven to 425°F (220°C). In a large Dutch oven, mix together the whole peeled tomatoes, chopped yellow onion, minced garlic, fresh thyme, unsalted butter, a drizzle of olive oil, kosher salt, and black pepper.

Transfer the Dutch oven to the preheated oven and roast uncovered for 40–45 minutes until the tomatoes soften and bubble.

While the tomatoes are roasting, tear sourdough bread into bite-sized pieces. Toss with melted butter and Italian seasoning, then bake for 13–15 minutes until golden brown.

Once roasted, stir in vegetable broth and simmer for 10 minutes. Then, purée the soup using an immersion blender until smooth.

Ladle the soup into bowls, top with sharp cheddar cheese and crispy croutons. Broil for about 2 minutes until cheese is bubbly.

Garnish with fresh thyme leaves and serve alongside warm, crusty bread.