Quick Beef Stew with Cauliflower Puree

Name: Quick Beef Stew with Cauliflower Puree
Ingredients: 1 head cauliflower, (2 to 2 1/4 pounds), trimmed and broken into large florets; 2 teaspoons olive oil; 1 1/2 pounds trimmed rib-eye or sirloin steak, cut into 1-inch cubes; Coarse salt and ground pepper; 6 cloves garlic, sliced; 2 tablespoons chopped fresh rosemary; 1 1/2 pounds mixed fresh mushrooms, (such as button, cremini, and stemmed shiitake), halved or quartered; 1 cup dry red wine; 1/4 cup balsamic vinegar; 2 tablespoons grated Parmesan cheese; 2 tablespoons butter