Slow Cooker Mediterranean Beef Stew

Name: Slow Cooker Mediterranean Beef Stew
Prep time: 25 min
Cook time: 8 h
Total time: 8 h 25 min
Cuisine: Mediterranean
Ingredients: 1-2 T olive oil (depends on your pan); 8 oz. sliced mushrooms; 1 small onion, diced in 1/2 inch pieces; 2 lbs. trimmed and diced chuck steak, cut in bite-sized pieces (see notes); 1 cup beef stock (see notes); 1 14.5 oz. can diced tomatoes with juice; 1/2 cup tomato sauce (see notes); 1/4 cup balsamic vinegar (see notes for lower-carb alternative); 1 can black olives, cut in half or fourths; 20 cloves garlic, cut in thin slices (optional, but good); 2 T finely chopped fresh rosemary (see notes); 2 T finely chopped fresh parsley (see notes); 1 T capers (or more); fresh ground black pepper and salt to taste