, cut into 1/2-in. pieces
MELT 3 tbsp butter in a large frying pan set over medium high. Add onion, mushrooms and garlic. Cook until onion is soft and no liquid from mushrooms remains, 7 to 8 min. Add barley and stir until glossy, about 1 min. Add wine and stir often until barley has absorbed all of the liquid, 3 to 4 min. Transfer to slow cooker insert.
STIR in squash, broth and 1/2 cup water. Cover and cook on low for 4 1/2 to 5 hours. Stir in remaining 1 tbsp butter and parmesan. If risotto is dry, add 1/4 cup water. Top with fried sage leaves, if desired.