Slow Cooker Beef Brisket with Onion Gravy

Name: Slow Cooker Beef Brisket with Onion Gravy
Prep time: 5 min
Cook time: 8 h
Total time: 8 h 5 min
Cuisine: British
Ingredients: 0.8 - 1 Kilo beef brisket; 3 - 4 small/medium brown or red onions (sliced); 6 cloves garlic (sliced); 2 sprigs fresh rosemary (or 1 teaspoon dried rosemary); 1 beef stock cube; Salt flakes and freshly ground pepper; 2 teaspoons cornflour; 2 teaspoons cold water; Meat juices and the cooked sliced onions/garlic