- 2 teaspoons vegetable oil, or as needed
- 1 small onion, chopped
- 1 large clove garlic, minced
- 2 (15.5 ounce) cans black beans, rinsed and drained
- 1 cup chicken stock
- 5 fresh sage leaves
- water to cover
- 1/4 cup freshly grated Parmesan cheese
- 2 tablespoons butter, softened
- 1/4 cup half-and-half
- 1/4 cup chopped green onion, or to taste
- 2 tablespoons grated Parmesan cheese, or to taste
- Heat oil in a saucepan over medium high heat. Fry onion and garlic in hot oil until onion is transparent, 5 to 7 minutes.
- Stir black beans, chicken stock, and sage leaves with the onion mixture; add just enough water to the saucepan to cover the beans completely. Bring the mixture to a boil, reduce heat to medium-low, and simmer until the beans are soft, about 15 minutes. Remove and discard sage leaves.
- Pour soup into a blender no more than half full. Cover and hold lid in place; pulse a few times before leaving on to blend. Puree in batches until smooth. Return soup to saucepan and place over low heat.
- Stir 1/4 cup grated Parmesan cheese and butter into the soup; cook and stir until melted, 2 to 3 minutes. Remove saucepan from heat and stir cream into the soup until smooth. Garnish with green onion and grated Parmesan cheese.