Slow Cooker Mushroom Barley Risotto

Name: Slow Cooker Mushroom Barley Risotto
Prep time: 10 min
Cook time: 3 h 10 min
Total time: 3 h 20 min
Cuisine: European, Italian, Mediterranean
Ingredients: 2 tablespoons extra-virgin olive oil; 1 large onion, finely chopped; Kosher salt and freshly ground black pepper; Kosher salt and freshly ground black pepper; 1 pound cremini mushrooms, sliced; 1 1/2 cups pearl barley; 4 sprigs fresh thyme; 8 ounces carrots, finely chopped; 3 cups lower-sodium vegetable broth; 1 ounce Parmesan, grated (2/3 cup); 1 tablespoon sherry vinegar; 1/4 cup chopped fresh flat-leaf parsley