Roast Beef Stuffed With Red Onions, Mushrooms and Barley | Oregonian Recipes

Ingredients

• 2 tablespoons extra-virgin olive oil, plus additional for preparing roast
• 3 medium red onions, diced (about 5 cups)
• 1 tablespoon granulated sugar
• 8 ounces fresh cremini mushrooms, roughly chopped
• Salt and freshly ground black pepper
• 2 tablespoons balsamic vinegar
• 2 teaspoons chopped fresh rosemary (divided)
• 1 cup cooked pearled barley (from 1/4-cup dried barley)
• 1 3- to 4-pound boneless rib-eye roast, top sirloin roast or sirloin tip roast
• 2 cloves garlic, minced