Hot Hamburger Sandwich - Cooking like a Boss

Traditional Canadian comfort food. It's a burger on top of a slice of bread covered in gravy. Much nicer than it deserves to be! Serve with garden peas and chips.

1 medium onions	dice	fry in burger pan until golden	fry until mushrooms golden	melt	stir in	stir in	season	return burgers to pan	cover and simmer until cooked through	top
oil
2cups 0.473l 473ml 0.833pint 31.5tbsp 94.6tsp mushrooms	slice
1tbsp 0.015l 15ml 3tsp 0.063cup 0.026pint butter
1tbsp 0.015l 15ml 3tsp 0.063cup 0.026pint flour
187 ¹⁄₂ml ³⁄₁₆l 12 ¹⁄₂tbsp 37 ¹⁄₂tsp 0.793cup 0.33pint beef broth
¹⁄₂tbsp 0.007l 7 ¹⁄₂ml 1 ¹⁄₂tsp 0.032cup 0.013pint marmite
burgers
250g ¹⁄₄kg 0.551lb 8.82oz minced beef	mix	form into 2 patties	brown	remove to plate
¹⁄₂tbsp 0.007l 7 ¹⁄₂ml 1 ¹⁄₂tsp 0.032cup 0.013pint worcestershire sauce
¹⁄₂tbsp 0.007l 7 ¹⁄₂ml 1 ¹⁄₂tsp 0.032cup 0.013pint garlic powder
salt
pepper
¹⁄₂tbsp 0.007l 7 ¹⁄₂ml 1 ¹⁄₂tsp 0.032cup 0.013pint onion powder
¹⁄₂ egg
oil
2 slices of white bread