Go Back
Vegan Roasted Tomato Basil Soup in bowls with spoons.

Easy Vegan Roasted Tomato Basil Soup

There’s just something about a steaming bowl of tomato soup that feels like a warm hug. This roasted tomato basil soup is cozy, deeply flavorful, and perfect for those chilly days when you want something satisfying yet light. It comes together with little effort, but the flavor will make you think it simmered all day.
Prep Time 10 minutes
Cook Time 50 minutes
Course Soup
Cuisine American
Servings 4 servings

Ingredients
  

  • 3 pounds Roma tomatoes
  • 1 yellow onion
  • 4-5 garlic cloves
  • 2 tablespoons olive oil
  • 2 tablespoons tomato paste
  • 8-10 basil leaves
  • Salt to taste
  • Black pepper to taste

Instructions
 

  • Preheat the oven to 400°F. Position a rack in the center of the oven. Line a large rimmed baking sheet with parchment paper for easy cleanup and to prevent sticking.
  • Rinse and dry the Roma tomatoes. Slice each one in half lengthwise and remove the stem/core if present. If you prefer a slightly less acidic soup, you can gently scoop out some of the seeds, but it’s not required.
  • Peel the yellow onion and cut it into quarters so the pieces roast evenly. Peel the garlic cloves and leave them whole so they soften and sweeten in the oven without burning.
  • Spread the tomatoes (cut-side up), onion quarters, and garlic cloves on the prepared baking sheet, leaving a little space between pieces for good airflow. Drizzle the olive oil evenly over everything.
  • Season generously with salt and black pepper. Toss lightly with your hands, then flip the tomatoes back to cut-side up so they caramelize nicely on top.
  • Roast for 35–45 minutes, rotating the pan halfway through. The tomatoes should look collapsed with lightly blistered edges, the onion should be tender with some browning, and the garlic should be soft and golden.
  • If anything is browning too quickly near the edges, move those pieces toward the center of the pan.
  • Remove the baking sheet from the oven and let the vegetables cool for about 10 minutes.
  • Tilt the tray and use a spatula to gather every bit of those flavorful juices and any caramelized bits - this is liquid gold for your soup.
  • Transfer the roasted tomatoes, onion, garlic, and all pan juices to a blender. Add the tomato paste. If your blender is small, work in batches.
  • For hot blending, vent the blender lid (remove the center cap) and cover the opening with a clean kitchen towel to allow steam to escape safely. Blend on high until completely smooth and velvety.
  • If the soup seems thicker than you like, blend in a splash of hot water, a little at a time, until it reaches your preferred texture.
  • Taste and add a pinch more salt and pepper if needed.
  • Pour the blended soup into a pot and set it over low to medium-low heat for 5–10 minutes, stirring occasionally. This brief warm-up helps the flavors round out without overcooking the fresh notes.
  • Stack the basil leaves, roll them up, and slice into thin ribbons (chiffonade).
  • Ladle into bowls, garnish with the basil, and add a tiny grind of black pepper or a light drizzle of olive oil, if you like. Enjoy!

Notes

Use the Right Tomatoes: Roma tomatoes work best because they’re meatier and less watery, which gives the soup a more concentrated flavor.
Don’t Skip Roasting: Roasting deepens the sweetness of the tomatoes and mellows the onion and garlic - making the soup taste like it simmered for hours.
Save the Pan Juices: Those caramelized bits and juices at the bottom of the roasting pan add a huge punch of flavor to the soup.
Blend in Batches if Necessary: If your blender is small, blend the soup in two rounds to avoid spills.
Adjust Thickness to Your Liking: Add a splash of vegetable broth or water for a thinner soup, or simmer uncovered for a few minutes to thicken.
Make It Creamy: Stir in a little coconut milk or cashew cream at the end for a richer texture without dairy.
Boost the Herbs: Fresh basil is key, but you can also add a touch of fresh oregano or thyme for extra depth.