Preheat the oven to 425°F (218°C). Place the halved tomatoes and red peppers on a baking sheet, cut side up, in a single layer. Drizzle with 1 tablespoon olive oil and sprinkle with 1 teaspoon salt. Lay a sprig or 2 of fresh basil on top of the vegetables.
3 lbs tomatoes halved or quartered, 2 large red bell peppers halved, 1 sprig fresh basil plus more for garnish
Roast in the oven for 45 minutes to one hour, or until they're slightly charred and very soft.
Remove from the oven and place red pepper halves in a bowl, covering tightly with plastic wrap to steam for a minimum of 10 minutes. Using your fingers, peel the skins off of the red peppers and roughly chop. Discard basil sprig.
In a large pot, heat the remaining 1 tablespoon olive oil over medium heat. Add the chopped onion and sauté until translucent. Add the garlic and cook for another minute or two.
1 large white onion diced, 3 large cloves garlic roughly chopped
Stir in the smoked paprika and chili flakes (if using). Add the roasted tomatoes and peeled peppers, including all their accumulated juices. Stir in the broth or water and baking soda, salt, pepper, and sugar. Bring to a simmer and continue simmering for 15 minutes to concentrate the flavors. Remove from heat and let cool for 10 minutes.
½ teaspoon smoked paprika, ¼ teaspoon dried chili flakes, 2 cups low sodium vegetable or chicken broth or water, ¼ teaspoon baking soda, ½ teaspoon salt or more to taste, ½ teaspoon black pepper, 2 teaspoon sugar
In a blender, puree the soup in batches until smooth. Return the pureed soup to the pot.
Stir in the milk or cream to achieve your desired consistency. Adjust seasonings to balance the flavors.
½ cup half and half cream or milk
Reheat the soup gently if needed. Serve hot, garnished with fresh basil or any optional toppings you prefer.