Posh burger with shoestring fries

Preparation time
1-2 hours

Cooking time
30 mins to 1 hour

Serves
Serves 2

By Matt Tebbutt
From Saturday Kitchen

Ingredients

For the onions

2 onions, thinly sliced
50g/1¾oz plain flour
1 tsp chilli powder
2 tbsp vegetable oil
pinch salt

For the shoestring fries

vegetable oil, for deep frying
2 potatoes, peeled and cut into shoestring fries
2 fresh thyme sprigs, leaves only and chopped
pinch salt

For the burger

400g/14oz chuck steak mince
80g/3oz minced beef fat
40g/1½ oz bone marrow
4 tbsp vegetable oil
4 burger cheese squares
salt and freshly ground black pepper

For the burger sauce

2 tbsp mayonnaise
1 tbsp tomato ketchup
1 tbsp American mustard
dash pickle juice from a gherkin jar
2 tbsp gherkins, chopped

To serve

2 brioche or cholla bread rolls, split
1 beef tomato, sliced
1 Little Gem lettuce, shredded
30g/1oz Parmesan, grated

Method

To make the onions, salt 1 onion in a bowl for 1 hour and then squeeze out any water. Place the seasoned flour and chilli powder on two plates, dip the squeezed onions in the flour and chilli powder and fry for 1–2 minutes until crispy.
Meanwhile, heat the oil in a saucepan over a medium heat. Add the remaining onions, cover with the lid and cook for 45 minutes until soft but with no colour. Set aside the two types of onions.
To make the shoestring fries, preheat a deep fat fryer to 180C. (CAUTION: hot oil can be dangerous. Do not leave unattended.) Place the fries in the fryer and cook for 3–4 minutes. Carefully transfer the fries to a plate lined with kitchen paper. Once drained, place in a bowl with the thyme, season with salt and set aside.
To make the burger, mix together the mince, fat and bone marrow in a bowl. Season with salt and pepper and shape into two patties. Heat the oil in a large, flat griddle pan, place the patties in the pan and cook for 1–2 minutes on one side. Flip the burgers, place the cheese squares on top and cook for 1–2 minutes, allowing the cheese to melt.
To make the burger sauce, mix all of the ingredients together in a bowl.
Serve the patties in the buns with the tomato, lettuce, Parmesan, two types of onions and burger sauce. Serve the shoestring fries on the side.