Method

1. Place the minced beef with the egg into a large bowl and mix thoroughly. Divide the mixture into 4 and shape into burgers. Leave to rest for 30 minutes in the fridge. 
2. Meanwhile prepare your toppings. For the beery onions, heat the butter in a small frying pan and add the onion and cook until golden.
3. Add the sugar and beer and cooked until reduced to a syrup. 
4. Cook the bacon until crispy and set aside. 
5. Once the burgers have rested, heat oil in a frying pan for around 4 minutes each side, until cooked thoroughly, turning occasionally. 
6. Assemble your ultimate burger, top the bottom slice of a burger bun with a dollop of BBQ sauce, then a beef burger topped with lettuce, tomato, bacon and cheese and spoon over the beery onions and press down the top half of the burger bun.