Preparation Heat olive oil in large pot over medium-high heat. Add onion and garlic. Sauté until onion is soft and golden , about 5 minutes. Add collard greens and sauté until wilted, about 4 minutes. Add sausage and sauté 5 minutes. Add broth and potatoes. Simmer soup uncovered until potatoes are tender, about 20 minutes. Transfer 2 cups soup (without sausage) to processor. Blend until smooth; return to pot of soup and bring to simmer. Mix in crushed red pepper. Season with salt and black pepper.
Preparation Heat olive oil in large pot over medium-high heat. Add onion and garlic. Sauté until onion is soft and golden , about 5 minutes. Add collard greens and sauté until wilted, about 4 minutes. Add sausage and sauté 5 minutes. Add broth and potatoes. Simmer soup uncovered until potatoes are tender, about 20 minutes. Transfer 2 cups soup (without sausage) to processor. Blend until smooth; return to pot of soup and bring to simmer. Mix in crushed red pepper. Season with salt and black pepper.