Wagyu burger

1.For pickled beetroot, combine ingredients with 1 litre water and 1 tsp salt in a saucepan over medium heat. Bring just to the boil, reduce heat to low, then simmer gently until beetroot are tender and liquid reduces to 400ml (1½-2 hours). When cool enough to handle, peel and thinly slice beetroot and set aside. Strain cooking liquid through a muslin-lined fine sieve into a saucepan, bring to the boil over medium heat and reduce to 260ml (10-12 minutes). Place beetroot in a sterilised jar, cover with liquid and seal. Pickled beetroot may be kept in refrigerator for up to 1 month. Makes 600ml.

2.Meanwhile, for caramelised onion, combine onion and oil in a saucepan, season to taste and stir frequently over low-medium heat until caramelised (45 minutes-1 hour). Set aside and keep warm.

3.Meanwhile, melt butter in a frying pan over medium heat, add onion and stir frequently until caramelised (35-40 minutes). Deglaze pan with Madeira, cool completely, then transfer to a bowl and add minces, breadcrumbs and egg and mix with your hands to combine. Season to taste. Mould into 4 patties, place on a tray, cover with plastic wrap and refrigerate for 30 minutes.

4.Preheat oven to 250C. Heat grapeseed oil in an ovenproof frying pan and sear burgers over medium heat until browned (1-2 minutes each side). Transfer to oven, roast for 1 minute, then top each burger with a cheese slice and roast until cheese just melts (1-2 minutes).

5.Meanwhile, preheat a grill on high heat and lightly toast cut-side of rolls, then spread with mayonnaise. Top roll bases with lettuce, burger, caramelised onion and beetroot. Sandwich with roll tops and serve immediately.