In a medium saucepan, combine grits and 3 cups water. Cook, stirring occasionally, until grits are tender, about 15 minutes.
While grits cook, heat oil in a large skillet over medium-high. Add sausage and cook, stirring to crumble, until sausage is cooked through and browned, 4 to 6 minutes. Use a slotted spoon to remove sausage from skillet. Reserve 2 tablespoons fat in skillet (discard any excess). Return skillet to medium heat.
Add scallion whites to hot fat and cook, stirring, until scallions have softened slightly, 2 minutes. Remove skillet from heat and whisk in cider vinegar. Place collards in a large bowl and pour warm dressing over greens. Use hands to crush dressing into greens until wilted, about 3 minutes. Season greens with salt and pepper, and stir in scallion greens.
Stir cheese into cooked grits and season with salt and pepper. Serve grits topped with collards and sausage.
Before her diagnosis, Caroline wrote a book on cakes called Cake Magic!. She started developing a birthday cake using her gluten-free mix found in that book. Check out other recipes she’s developing for her new life—and the stories behind them—on her blog, The Wright Recipes. Her next book, Catalan Food, written with chef Daniel Olivella, comes out in early September from Clarkson Potter.