Make shells and set aside

In a large saucepan or Dutch oven, cover beans with water and soak overnight

Or combine the beans and water in a large pot, bring to a boil and cook, uncovered, 1 minute

Then remove pan from the heat, cover and let stand 1 hour

Drain well

Heat olive oil in a Dutch oven

Add the prosciutto, onion, celery and carrot and cook over low heat, stirring occasionally, until tender

Add the garlic and cook 1 minute longer

Add the drained beans, 8 cups of water, tomatoes and bay leaf

Bring to a boil, reduce the heat to low and cook, uncovered, until the beans are very tender and the soup is thickened, about 2 hours

Stir in the pasta and salt

Simmer, stirring often, until the pasta is al dente

Stir in 1-1/2 tablespoons of the Parmesan cheese

Serve in bowls and top with remaining Parmesan.