On a sheet of waxed paper, combine the flour, 1/4 teaspoon of the salt, and the pepper

Dredge the sausage in the flour mixture, shaking off the excess

In a non-stick Dutch oven, heat 1 teaspoon of the oil until hot but not smoking over medium heat

Add the sausage, in batches if necessary, and cook until lightly browned on all sides, about 6 minutes

Transfer the sausage to a plate and set aside

Add the remaining 1 teaspoon oil to the pan

Add the onion and cook, stirring frequently, until the onion has softened, about 5 minutes

Stir in the broth, 1/2 cup of water, and the beans. Return the sausage to the pan

Bring to a boil over medium-high heat, reduce to a simmer, cover, and cook for 10 minutes

Stir in the squash, vermicelli, and remaining 1/4 teaspoon salt

Return to a boil, reduce to a simmer, and cover again

Cook until the vermicelli is just tender and the sausage is cooked through, about 7 minutes longer

Remove from the heat and stir in the sour cream and dill

Divide the chicken fricassee among bowls and serve.