Wagyu Burger

Wagyu burger

Serves 4
Cooking Time Prep time 25 mins, cook time 2hrs 30 mins (plus chilling) 

30 gm	unsalted butter
3	onions (about 600gm), coarsely chopped
30 ml	Madeira
400 gm	wagyu, coarsely minced (see note)
100 gm	wagyu fat, coarsely minced (see note)
50 gm	dried fine breadcrumbs
1	egg, lightly whisked
2 tsp	grapeseed oil
4	thin slices of vintage cheddar (80gm)
4	brioche rolls, split (see note)
To serve:	mayonnaise
1	baby cos, outside leaves discarded, leaves separated
Pickled beetroot
500 gm	beetroot (about 3), trimmed, washed
200 ml	red wine
100 ml	ruby port
100 ml	cabernet sauvignon vinegar
50 gm	white sugar
Carmelised onion
2	onions, thinly sliced
2 tsp	grapeseed oil

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.