Heat the vegetable oil in a large pot over medium heat. Cook the Italian sausages in the hot oil, turning occasionally, until browned on the outside and no longer pink in the center, 10 to 15 minutes. Set aside to cool; remove all but 1 tablespoon of grease from the pot.

Stir the garlic, onion, carrot, potato, and celery into the hot fat. Cook until the vegetables are tender and the onion has turned translucent, about 7 minutes. Stir in the tomato paste until no lumps remain; pour in the red wine. Bring to a boil over high heat and cook until the liquid has reduced by half, stirring frequently to dissolve the brown bits from the bottom of the pan. Add the beef broth, black beans, and diced tomatoes. Reduce heat to medium-low, cover, and simmer 1 hour.

Cut the cooled sausage into 1/2-inch thick slices. Stir the sausage into the soup along with the rotini pasta, spinach, and dried oregano. Simmer until the pasta is tender, 7 to 10 minutes. Stir in the chopped basil and season to taste with salt and pepper before serving.