Brown the sausage

• Melt the butter in a large skillet or shallow pan over medium heat.
• Add the crumbled Italian sausage and cook until well browned.

Build the base

• Stir in the shallot, garlic and red pepper flakes and sauté until softened and fragrant.
• Add the tomato paste and cook, stirring, until it darkens to a deep red color.
• Deglaze with a splash of chicken broth, scraping up the browned bits.

Simmer the beans

• Add the cannellini beans, the remaining chicken broth, the half-and-half and the Parmesan rind.
• Stir to combine and simmer uncovered on low heat until the beans soften and the sauce thickens.
• Lightly mash some of the beans for a creamier texture.

Finish the sauce

• Remove the Parmesan rind and season with salt and pepper.
• Stir in a generous amount of grated Parmesan until glossy and creamy.

Toast the bread and serve

• While the beans simmer, toast the sliced sourdough garlic bread.
• Top the beans with Parmesan or mozzarella and fresh parsley.
• Serve warm with the toasted bread and extra Parmesan.