Slow-Roasted Tomato and Basil Soup with Garlic Croutons

By AislePrompt Editorial · Published 2026-05-14 · Updated 2026-05-14

A rich, velvety soup made from slow-roasted tomatoes and fresh basil, served with crunchy garlic croutons for a comforting meal. This French-inspired soup recipe (vegetarian), ready in about 150 minutes, pairs roma tomatoes, olive oil, garlic cloves for a weeknight-friendly dinner that comes together with one pan and minimal cleanup. Each serving lands at about 180 calories and feeds 6, so it slots cleanly into a weekly meal plan and pairs well with a quick salad or grain on the side. Tap "Plan a meal with the AI" below to drop this recipe into your week and send the ingredients straight to Instacart. Nutrition values are approximate, calculated from USDA FoodData Central (fdc.nal.usda.gov) — verify against ingredient labels for any health-driven dietary plan.

Ingredients

• 3 lbs, halved roma tomatoes
• 4 tbsp olive oil
• 8 whole cloves garlic cloves
• 1 large, chopped yellow onion
• 4 cups vegetable broth
• 1/2 cup packed fresh basil leaves
• 2 tsp salt
• 1 tsp black pepper
• 1 cup small cubes baguette slices
• 2 tbsp unsalted butter

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Instructions

1. Step 1: Preheat oven to 300°F. Toss 3 lbs halved roma tomatoes and 8 whole garlic cloves with 3 tbsp olive oil, 1 tsp salt, and 1/2 tsp black pepper on a large baking sheet. Roast for 2 hours until tomatoes are deeply caramelized and shriveled.
2. Step 2: In a large pot, heat 1 tbsp olive oil over medium heat. Add 1 chopped large yellow onion and sauté for 8 minutes until translucent and soft.
3. Step 3: Add the roasted tomatoes and garlic (squeezed from skins) to the pot along with 4 cups vegetable broth, 1/2 cup packed fresh basil leaves, 1 tsp salt, and 1/2 tsp black pepper. Simmer for 15 minutes to meld flavors.
4. Step 4: Use an immersion blender to puree the soup until smooth and velvety. Adjust seasoning to taste.
5. Step 5: Meanwhile, melt 2 tbsp unsalted butter in a skillet over medium heat. Add 1 cup small baguette cubes and 2 minced garlic cloves, toasting for 3-4 minutes until golden and fragrant. Stir frequently to avoid burning.
6. Step 6: Serve the soup hot topped with garlic croutons for crunch and extra garlic flavor.