Easiest ever beef casserole

Ingredients
• 515g Diced Beef Casserole
• 1 onion, roughly chopped
• 1 leek, trimmed and sliced
• 1 stick celery, thickly sliced
• 150g carrots, thickly sliced
• 125g mushrooms, halved
• 2tsp mixed dried herbs
• 2 reduced-salt beef stock cubes
• 1tbsp tomato purée
• 2tbsp brown sauce
• 250ml brown ale, beer or water
• 1tbsp cornflour mixed with 2tbsp water
• Mashed potato, to serve
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• Steps
• 1. Preheat the oven to 150C/ 130C Fan/Gas 2. Put the beef in a large casserole dish with the vegetables and gently mix together.
• 2. Sprinkle on the herbs. Heat 350ml water in a pan until simmering. Remove from the heat and add the stock, puree and brown sauce, then stir until dissolved. Add the ale, beer or water.
• 3. Pour over the meat. Cover and bake for 4 hours. Stir in the cornflour paste, cover and return to the oven for 5 minutes. Serve with mash.