1 Tbs. extra-virgin olive oil
1 medium yellow onion, finely chopped (1-1/2 cups)
1 medium carrot, peeled and finely chopped (3/4 cup)
1 medium celery stalk, finely chopped (3/4 cup)
1-1/2 tsp. minced fresh rosemary
2 Tbs. tomato paste
2 large cloves garlic, minced (1 Tbs.)
1 quart homemade or lower-salt vegetable broth
Two 15-oz. cans cannellini beans, rinsed and drained
6 oz. Lacinato kale, center ribs removed, leaves chopped (about 4 firmly packed cups)
1 Parmigiano-Reggiano rind (1x3 inches; optional)
1-1/2 tsp. cider vinegar
Kosher salt and freshly ground black pepper