Hamburger Steak with Onions

Ingredients

• • ½ cup (40 g) panko breadcrumbs
  • ¼ cup (60 ml) milk
  • 1 ½ lb (675 g) medium-lean ground beef
  • 2 eggs, beaten
  • 1 ½ tsp sweet smoked paprika
  • 1 tsp cracked black pepper
  • 2 tbsp butter
  • 2 onions, thinly sliced
  • 2 tbsp (30 ml) apple cider vinegar
  • 2 cups (500 ml) beef broth
  • 2 tbsp dark toasted flour (see note)
  • 1 tbsp (15 ml) Worcestershire sauce
  • 1 tbsp (15 ml) prepared mustard