Roasted Tomato & Basil Soup with Harissa

The secret to a restaurant-quality tomato soup isn’t long simmering on the stove, but aggressive roasting in the oven. By exposing the tomatoes to 200°C (400°F) dry heat, we concentrate the flavors and trigger the Maillard reaction, producing natural sweetness and umami.

Instructions

1. Roasting (The Base)

Preheat the oven to 200°C (400°F) on convection setting, or 220°C (425°F) conventional. Halve the tomatoes and place them cut-side down on a large baking sheet. Scatter the roughly chopped onions among them. Slice the top (about 0.5 cm) off the whole head of garlic to expose the cloves, drizzle a drop of olive oil inside, wrap it in aluminum foil, and place it on the tray. Generously drizzle the tomatoes with olive oil, sea salt, and black pepper. Roast everything in the oven for 35 to 40 minutes, until the edges of the tomatoes are dark and blistered.

2. Blooming the Harissa

Heat 2 tablespoons of olive oil in a heavy-bottomed soup pot over medium-low heat. Add the harissa paste and sauté for 2 minutes. This process (“blooming”) activates the heat and releases the complex spices in the paste into the oil, resulting in a much rounder, fuller flavor than if added to the liquid later.

3. Combining & Deglazing

Remove the baking sheet from the oven. Squeeze the soft-roasted garlic cloves out of their skins directly into the soup pot with the harissa. Add the roasted tomatoes, onions, and all the released cooking juices from the tray. (Pour a small splash of broth onto the hot baking tray and use a spatula to scrape up the stuck-on, browned bits—this is pure flavor!—and pour it into the pot).

4. Puréeing and Finishing

Pour in the hot vegetable broth and bring the mixture to a gentle boil. Simmer for 10 minutes to allow the flavors to integrate. Remove the pot from the heat. Add half of the fresh basil (including stems). Purée the soup with an immersion blender until silky smooth. Taste carefully and adjust the seasoning with salt or a teaspoon of sugar if the tomatoes are too acidic.

5. Plating

Serve the soup hot in shallow bowls. Garnish with the remaining fresh basil leaves (finely chopped) and a generous drizzle of high-quality extra virgin olive oil.