Wagyu burger | Gourmet Traveller

Ingredients

• 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