Mushroom Swiss Patty Melt with Caramelized Onions
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How to Make Mushroom Swiss Patty Melt with Caramelized Onions
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This is an amazing way to use up leftover burgers or meatloaf (the photo above used leftover meatloaf)… but completely worth cooking it up fresh! Caramelizing the onions is a slow process but adds a beautiful sweet & rich flavor to the burgers!
While rye is the traditional choice for a patty melt, I really enjoy the flavor and texture of sourdough so that’s what I used!
- 8 Slices Sourdough Bread (or rye bread)
- Grainy Mustard (optional)
- 16 Slices Swiss Cheese
- 12 Large Mushrooms , sliced
- 1 teaspoon soy sauce
- 2 Onions , sliced
- 1/2 tablespoon brown sugar
- 1 lb . Lean Ground Beef
- 2 tablespoons finely chopped onion
- Frozen burger patties
- Left over meatloaf or hamburgers
Over low heat, combine sliced onions, 1 tablespoon of butter and brown sugar.
Slowly cook onions stirring until golden. This can take a up to 25 minutes… but they can cook slowly while you prepare the rest of the ingredients.
If using frozen patties, cook according to package directions. For fresh beef, combine beef, onion and pepper. Divide into thin 4 patties (remember they will shrink in size a bit when cooked).
Over medium-high heat, cook the patties 2 at a time for 3 minutes on each side until no pink remains. Set aside.
Toss sliced mushrooms with soy sauce and cook over medium high heat until juices have been released. Set aside.
Lightly butter both sides of the bread slices. On a griddle or frying pan, grill the bread on one side until lightly browned. Remove from heat.
On the already grilled side, spread a very thin layer of grainy mustard. Create your sandwich adding the ingredients in this order: 1 slice cheese, onions, meat patty, mushrooms, slice of cheese, bread
Grill on medium low heat until bread is browned and cheese is melted.
(Nutrition information provided is an estimate and will vary based on cooking methods and brands of ingredients used.)