Casserole with minced meat and potatoes

Ingredients for Casserole with minced meat and potatoes

• 1.1 lb (500 g) ground beef
• 2.2 lb (1 kg) potatoes
• 1 egg
• 9 fl oz (250 ml) milk
• 3.5 oz (100 g) butter
• 1 onion
• 1.8 oz (50 g) cheese
• Salt, pepper