Heat a saucepan over medium heat. Add the oil, onion and thyme. Sweat the onion until translucent (about 5 minutes). Add the peppers, cover with water, and bring to a simmer. Cook for about 5 minutes for the flavors to meld. Allow to cool before pureeing. To chill the soup fast, place it in a bowl set inside another bowl that’s filled with ice water.

While the soup is cooking, make the spiced yogurt. Stir together the yogurt, coriander, and sriracha. Season to taste with salt and pepper.

While the soup is cooking, bring a small pot of salted water to the boil. Cook the stelline according to package directions. Drain and reserve.

When the soup is chilled, stir in the stelline. Taste and adjust seasoning. Divide between 4 bowls. Place a dollop of the yogurt in the middle of the bowl and sprinkle with the basil.