- 2 tablespoons olive oil
- 1 large onion, diced
- Kosher salt
- Freshly ground black pepper
- 4 cloves garlic, minced
- 1/4 teaspoon red pepper flakes, plus more as needed
- 1/4 cup tomato paste
- 8 cups unsalted chicken broth
- 2 cups dry ditalini pasta
- 1 1/2 pounds uncooked peeled and deveined medium shrimp
- 1/4 cup loosely packed fresh basil leaves
Heat the oil in a 5-quart or larger Dutch oven over medium-high heat until shimmering. Add the onion, season with salt and pepper, and sauté until translucent and softened, about 5 minutes. Add the garlic and pepper flakes and sauté until fragrant, about 1 minute more.
Add the tomato paste and sauté until the paste has deepened in color, about 2 minutes. Stir in the chicken broth. Bring to a boil, then reduce the heat to low to simmer uncovered for 10 minutes.
Add the pasta and continue to simmer until it’s al dente, about 10 minutes or according to package instructions. Taste and season the soup with salt, pepper, and red pepper flakes as needed.
Stir in the shrimp and simmer until they are pink and opaque, 3 to 4 minutes. Thinly slice the basil and serve the soup immediately, as it does not keep well, with basil sprinkled over each bowl.