Recipe: Steak Burger with Béarnaise Sauce on a Classic Unseeded Bun

Ingredients

• 10 Unseeded burger bun
• 10 steaks (not too thick)
• Mixed lettuce
• 2 egg yolks
• 1 teaspoon good quality mustard
• 1 teaspoon apple cider vinegar
• 150 ml olive oil
• 1 teaspoon béarnaise-essence (flavour)
• 1 tablespoon finely chopped tarragon
• Salt
• pepper
• 500g fresh mushrooms, sliced
• 4 onions, sliced
• 1 chili, finely chopped
• 2 teaspoons cane sugar
• 2 tablespoons olive oil
• 1 tablespoon lemon