Heat 2 tablespoons olive oil in a large dutch oven over medium-high heat.
Add the sausage and cook, breaking up into chunks until fully browned.
Add the onion, garlic, and fennel seeds, and cook for 2 minutes, just until fragrant.
Add the chile flakes, broth and tomatoes with their liquid. Bring to a boil, then lower heat and let simmer for 40 minutes, stirring occasionally and breaking up the tomatoes with the spoon.
Add the rice and simmer an additional 15 minutes, or until rice is tender.
Remove from heat and stir in the kale, stirring until wilted from the heat of the soup.
Taste and adjust seasoning with kosher salt and black pepper, as desired.
Serve in bowls topped with generous spoonfuls of shredded cheese.
