Cheesy Cauliflower Mash with Sausage and Brussels Sprouts

Bring a large pot of water to a boil and generously season with salt. Add cauliflower and cook until tender, about 10 to 15 minutes. Smaller pieces will cook faster. Drain cauliflower in a colander and transfer back to the pot over medium-high heat; stir in stock, white wine, and season with 1 teaspoon salt. Cover pot and bring to a boil; simmer for 5 minutes. Add cream and smash with a potato masher until smooth. Fold in cheese just before serving. Meanwhile, in a large skillet over medium-high heat sauté sausage until golden, about 2 minutes. Add 1 tablespoon olive oil, brussels sprouts, 1/2 teaspoon salt, and 1/2 teaspoon black pepper. Sauté until brussels sprouts are tender, about 2 to 3 minutes. Mix in parsley. Serve sausage and brussels sprouts over cauliflower mash and drizzle with olive oil. Serve immediately.