PreparationFor soup: Place Great Northern beans in large pot. Pour enough water over beans to cover by 4 inches. Let soak overnight. Drain beans and return to pot. Pour enough water over beans to cover by 4 inches. Add 2 bay leaves and bring to boil. Reduce heat to medium-low. Add 3 tablespoons olive oil and fresh rosemary sprigs and simmer uncovered until beans are barely tender, about 30 minutes. Heat 3 tablespoons olive oil in another large pot over medium heat. Add russet potato pieces and sauté until brown in spots, about 8 minutes. Add half of garlic and sauté until beginning to color, about 3 minutes. Add 6 cups chicken st0ock and boil until potato pieces are falling apart, about 10 minutes. Pour beans and cooking liquid into potato mixture. Bring to boil; reduce heat and simmer just until beans are tender, about 10 minutes. Season soup generously with salt and pepper. (Soup can be prepared up to 2 days ahead. Cool slightly, then cover and refrigerate. Bring to simmer before continuing, thinning with additional chicken stock if necessary.) For parmesan oil: Blend 2/3 cup grated Parmesan cheese and 1/4 cup olive oil in processor until smooth. (Parmesan oil an be prepared 1 day ahead. Cover oil and refrigerate.) Stir 2 bunches arugula into soup. Heat remaining 2 tablespoons olive oil in heavy small skillet over medium heat. Add remaining chopped garlic and dried crushed red pepper; sauté until golden. Add to soup and simmer 5 minutes. Stir Parmesan oil into soup. Season soup to taste with salt and pepper.
PreparationFor soup: Place Great Northern beans in large pot. Pour enough water over beans to cover by 4 inches. Let soak overnight. Drain beans and return to pot. Pour enough water over beans to cover by 4 inches. Add 2 bay leaves and bring to boil. Reduce heat to medium-low. Add 3 tablespoons olive oil and fresh rosemary sprigs and simmer uncovered until beans are barely tender, about 30 minutes. Heat 3 tablespoons olive oil in another large pot over medium heat. Add russet potato pieces and sauté until brown in spots, about 8 minutes. Add half of garlic and sauté until beginning to color, about 3 minutes. Add 6 cups chicken st0ock and boil until potato pieces are falling apart, about 10 minutes. Pour beans and cooking liquid into potato mixture. Bring to boil; reduce heat and simmer just until beans are tender, about 10 minutes. Season soup generously with salt and pepper. (Soup can be prepared up to 2 days ahead. Cool slightly, then cover and refrigerate. Bring to simmer before continuing, thinning with additional chicken stock if necessary.) For parmesan oil: Blend 2/3 cup grated Parmesan cheese and 1/4 cup olive oil in processor until smooth. (Parmesan oil an be prepared 1 day ahead. Cover oil and refrigerate.) Stir 2 bunches arugula into soup. Heat remaining 2 tablespoons olive oil in heavy small skillet over medium heat. Add remaining chopped garlic and dried crushed red pepper; sauté until golden. Add to soup and simmer 5 minutes. Stir Parmesan oil into soup. Season soup to taste with salt and pepper.