Fried egg smash burgers

For the red onion jam, heat the butter and olive oil in a saucepan over a medium-low heat. Add the sliced onions and a pinch of salt and cook slowly for 20-25 minutes, until they have cooked down and are soft and golden, stirring occasionally

Stir in the brown sugar and balsamic vinegar and cook for another 5-10 minutes until the onions are caramelised and jammy, adding the thyme for the last minute. Taste, adjust the seasoning and set aside – this keeps well in the fridge for up to 3 days

For the burger sauce, place the mayonnaise, Dijon mustard and ketchup in a bowl and stir to combine. Thoroughly mix in the remaining ingredients with a pinch of salt and black pepper until smooth then set aside in the fridge for at least 20 minutes to let the flavours develop

For the smash burgers, season the beef mince with salt and pepper and divide it into 8 balls – avoid overworking the mince

Preheat a heavy-based frying pan on a medium-high heat with a little oil until hot

Cook the bacon in the pan, turning occasionally until crispy and cooked through. Set aside on kitchen paper to drain

Meanwhile, working in batches to avoid overcrowding, place 2 beef balls in the pan, alongside the bacon. Smash each ball down firmly with a burger press to create thin patties. Cook for 1-2 minutes to develop a crispy edge, pressing down again with the weight if they start to curl up. Flip the patties, season lightly with salt and add 1 slice of cheese to 1 patty. Add a tbsp of water into the pan, cover and cook for a final minute to melt the cheese, then remove to a warm place and repeat with the remaining patties – remove any residual beef or bacon with a slotted spoon to keep a clean pan and prevent burning

Once the patties and bacon are resting, reduce the heat to medium and add the olive oil to the pan along with the rendered beef and bacon fat. Crack in the eggs and fry them until the edges are crispy but the yolks remain runny. Season with salt and remove to drain on kitchen paper

Lightly fry the cut sides of the brioche buns in the residual fat in the pan until golden, then remove

To serve, spread some of the burger sauce on the bun bases. Stack 2 smashed patties on top of each (1 without cheese and 1 with) and spoon over a generous layer of caramelised onion jam. Add slices of pickle, 2 slices of crispy bacon per burger and top with the crispy fried eggs. Put the lids on top and serve immediately