Step 1

For the onion jam, heat 3 tbsp olive oil in a wide-based saucepan over medium heat. Cook onions until they are soft and browning.

Step 2

Add wine and vinegar, then reduce the liquid until syrupy and the consistency resembles jam. Cool before serving.

Step 3

Heat the oven to 170°C. Lay bacon on a lined baking tray and cook for 6-10 minutes, depending on thickness, or until golden and very crispy. Transfer to paper towel to drain fat.

Step 4

Heat a frying pan or grill until very hot. Grill burgers for 4 minutes on each side, then turn again and cook for another 4 minutes.

Step 5

Top with cheese and cover for 2 minutes to allow it to melt.

Step 6

Grill bread and assemble burger with a generous amount of jam on the bottom, 2 layers of bacon, burger, and lettuce.