Preheat oven to 425°F. Cut ripe tomatoes in half, toss with 2 tablespoon olive oil and a pinch of salt. Spread cut-side up on a baking sheet. Roast for 20-25 minutes until edges caramelize and skins wrinkle.
2 to 2.5 lbs ripe tomatoes, 3 tbsp olive oil
Heat 1 tablespoon olive oil in a large pot over medium heat. Add diced onion and cook for 5-7 minutes until translucent. Add minced garlic and cook 1 minute until fragrant but not browned.
1 medium onion, 3 to 4 cloves garlic, 3 tbsp olive oil
Add roasted tomatoes with pan juices and 3 cups broth to the pot. Bring to a gentle simmer, reduce heat to low, and cook uncovered for 20-30 minutes to blend flavors.
2 to 2.5 lbs ripe tomatoes, 3 cups vegetable broth
Remove soup from heat and stir in fresh basil leaves. Blend soup using an immersion blender until completely smooth. Alternatively, transfer to a regular blender in batches, cooling slightly first to avoid steam burns.
1 cup fresh basil
Return soup to low heat if using a blender. Taste and add salt, black pepper, and optional sugar to balance acidity. For a creamy soup, temper ½ cup cream by whisking in ¼ cup warm soup first, then stir into the pot.
salt, black pepper, 0.5 cup cream or milk, 1 to 2 tsp sugar
