If cooking in the crockpot – Add everything into the crockpot and cook for 6 hours on high, 8-9 hours on low.
If cooking in the casserole dish – preheat oven to 200°C/ 390°F and cook for 1.5-2 hours. If you're not freezing the meal before hand, you can fry off the beef in a pan for 4 minutes before adding it to the casserole dish.
To thicken, stir the flour and water together to form a paste, and slowly mix into the beef and sauce while it's still hot. Stir it around and it will thicken up.