- Heat a large saucepan or Dutch oven over medium-high heat. Add ground sausage, breaking up the meat. Cook, stirring occasionally until browned and cooked through about 5 minutes.
- Using a slotted spoon, remove cooked sausage and allow to drain on a plate covered with paper towels. Discard drippings, but do not wash pan.
- Melt butter over medium heat. When bubbling subsides, add onion and carrot. Cook until onion begins to brown on the edges and becomes somewhat translucent.
- Stir garlic into onion and carrot mixture. Cook one minute. Add red wine vinegar and cook until syrupy, scraping up browned bits-about 1 minute.
- Stir in oregano, basil, sage and red pepper flakes. Pour in stock and heavy cream. Increase heat to medium-high.
- When soup reaches a simmer, add cauliflower and turn heat down to medium-low. Simmer uncovered until cauliflower is fork-tender, about 10 minutes. Stir in kale and cooked sausage. Cook 1 to 2 minutes longer, or until kale wilts and the sausage is reheated.
- Season to taste with salt and pepper. The amount of salt needed may vary due to variation in brands of broth.