Ingredients

Active time 10 minutes, start to finish 30 minutes

1/4 cup olive oil
1 cup frozen chopped onions (about 6 ounces)
4 garlic cloves, chopped
1 celery rib, halved lengthwise and thinly sliced crosswise
2 carrots, halved lengthwise and thinly sliced crosswise
5 1/4 cups reduced-sodium chicken broth (42 fluid ounces)
2 1/2 cups water
20 refrigerated or frozen precooked meatballs (15 to 20 ounces; do not thaw if frozen)
Two 14-ounce cans small white beans, drained and rinsed
5- to 6-ounce bag baby spinach, coarsely chopped
1/2 cup finely grated Parmigiano-Reggiano cheese
Accompaniment: finely grated Parmigiano-Reggiano

Directions

Heat 2 tablespoons oil in a 5- to 6-quart pot over high heat until hot but not smoking, then cook onions, garlic, celery and carrots, stirring occasionally, until onions are pale golden, about 4 minutes. Stir in broth and water and bring to a boil, covered.

Meanwhile, heat remaining 2 tablespoons oil in a 12-inch heavy skillet over high heat until hot but not smoking, then saute meatballs (do not thaw if frozen), turning occasionally, until browned all over, about 3 minutes.

Add meatballs to soup along with beans, and briskly simmer, covered, stirring occasionally, until vegetables are tender and meatballs are heated through, about 15 minutes. Stir in spinach, cheese, salt and pepper and simmer, uncovered, until spinach is wilted, about 1 minute.

Makes 4 servings.