2 tbsp (30 mL) White wine, dry sherry or chicken broth
1 tsp (5 mL) Worcestershire sauce
1 Clove garlic, finely chopped
1/2 tsp (2 mL) Each salt and pepper
1/4 tsp (1 mL) Dried thyme leaves
2 tbsp (30 mL) Cold butter, cut into cubes
4 Janes Ultimate Chicken Burgers
4 Slices Gruyère or Swiss cheese
8 Thick slices French bread
Preheat the grill to medium. Layer two 24-inch (60 cm) long pieces of foil on a flat work surface. Arrange the onions on half the foil, in a thin, even layer. Drizzle the wine and Worcestershire sauce over top. Sprinkle the garlic, salt, pepper and thyme over the onions and dot with butter. Fold the foil over to make a square-shaped packet; crimp the edges to seal tightly.
Place the packet on the grill. Cook, turning once, for 10 minutes. Increase the heat to medium-high. Add the burgers to the grill. Cook, turning the packet occasionally and the burgers once, for 15 minutes. Place a slice of cheese on each burger. Cook for an additional 3 to 5 minutes or until melted. Meanwhile, place the bread on the grill to lightly toast on both sides.
Being careful to avoid steam, cut open the foil packet. Place each burger on a slice of toasted bread and top with a mound of cooked onions. Dress the burgers with additional toppings as preferred before capping with remaining slices of bread.
Indoor Method: Melt the butter in a large, heavy skillet set over medium low heat. Add the onions, thyme, salt and pepper; cook, stirring occasionally, for 15 to 20 minutes or until very soft and golden. Increase the heat to medium-high. Stir in the garlic, half of the broth and the wine (if using). Cook, stirring often and adding extra broth as needed, until onions are deeply browned. Stir in 2 tbsp (30 mL) broth and remove from the heat. Meanwhile, prepare the burgers in an oven or skillet according to package directions; add the cheese during the last 2 to 3 minutes.
Stir 1 part grainy Dijon mustard with 2 parts mayonnaise to spread over toasted bread to make the burger extra saucy.