Mix the minced meat with half of the beer sauce and form a patty.
Take 2 rolls and cut in half into squares, brown for a few moments on a hot griddle with a few drops of oil and toast for 1 minute under the grill of the oven.
Grill the burger for 2 minutes on each side.
Halfway through cooking, season with salt and pepper and add half of the diced cheese on top. Grill the bacon slices until they are nice and crispy.
Mix the remaining beer sauce with the barbecue sauce and spread on the inside of the roll. Add the tomato slices, the hamburger when still quite hot, the bacon, the remaining cheese cubes, the caramelised onion, the julienne lettuce and the gherkins.
Garnish with a trickle of mayonnaise and serve immediately.