Step 1

Preheat the oven to 425ºF (220ºC).

Step 2

Trim the stems and cores from the tomatoes, then roughly chop. Remove the seeds and ribs from the bell pepper and slice. Peel and quarter the onion. Smash and peel the garlic cloves. Add everything to a baking sheet and drizzle with the olive oil. Season with salt and pepper.

Step 3

Roast for 30 minutes, until the vegetables are browned on the edges and fragrant.

Step 4

Transfer the roasted vegetables to a slow cooker. Add the oregano, thyme, tomato paste, and vegetable stock.

Step 5

Cover and cook on high for 2 hours.

Step 6

Using an immersion blender or a standing blender, puree the soup until creamy.

Step 7

Stack and roll the basil leaves, then thinly slice. Add some to the soup and stir to incorporate.

Step 8

Ladle the warm soup into bowls and garnish with more basil.

Step 9

Enjoy!