1-Start by preheating your oven to 400 degrees Fahrenheit for that essential roasting step. Toss the 3 pounds of fresh ripe plum tomatoes with 1/4 cup olive oil, salt, and pepper, then arrange them in a single layer on a baking sheet and roast for 45 minutes. This process brings out their natural sweetness and adds a rich depth to the soup.

2-Next, in a large pot over medium heat, sauté the 2 chopped yellow onions (about 2 cups) and 5 minced garlic cloves with the remaining 2 tablespoons olive oil, 2 tablespoons butter, and 1/4 teaspoon red pepper flakes until the onions turn translucent and begin to brown, which takes about 10 minutes. For more tips on sautéing, visit our sauté techniques guide on the blog.

3-Then, add the one 28-ounce can of whole plum tomatoes with their juice, 2 cups packed and chopped fresh basil, 1/2 teaspoon thyme, and 4 cups chicken or vegetable broth to the pot, along with the roasted tomatoes and their pan juices. Bring everything to a boil, reduce the heat, and simmer uncovered for 40 minutes to blend the flavors.

4-After simmering, taste and adjust the salt, pepper, and herbs as needed for your preference. Puree the soup using a blender or immersion blender until it’s smooth and creamy. Finally, serve it hot, topped with grated parmesan cheese and fresh basil as optional garnishes, maybe alongside cheesy bread for a complete meal.