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It almost never fails, when we are traveling and stop at a local microbrewery or other casual eateries, Melissa is going to order a burger. We’ve tried all varieties of burgers that include a variety of ground meats, but as we get older we keep looking for healthier alternatives. One of the most delicious and satisfying is the old standby: the turkey burger. It’s nice to add some other elements to bump up the umami on what can be a rather bland turkey burger, so this caramelized onion mushroom Swiss turkey burger is one of our tried and true favorites.
Everything can be made ahead, from the caramelized onions to the turkey patties themselves. This will definitely speed up the preparation time, especially the onions as true caramelized onions take some time to make properly.
Key Ingredients and Substitutions
Burgers are no longer just fast food, and the investment you make in preparation time and ingredients will determine how memorable your creations are. None of the ingredients are especially expensive, so you might as well buy the best you can find. Turkey by itself can be somewhat bland and dry, so skipping the herbs and spices is not recommended. Feel free to experiment with some of your own favorite sauces and spices to tailor the flavor to your own personal tastes.
The full ingredient list and measurements are listed in the printable recipe below.
- Turkey. There is some variation in the quality and price of ground turkey, but even the best isn’t all that expensive. Deciding the best lean-to-fat ratio may be your biggest conundrum, especially if you are health-focused. While you can purchase 99% lean ground turkey, we really recommend something in the 80-85% range so your burgers don’t come out too dry and flavorless.
- Caramelized Onions. This is a simple recipe that requires an investment in patience to yield the best results. It doesn’t take much longer to make a double or triple batch, and they freeze and reheat very well. Starting from scratch will more than double the preparation time, so do your future self a favor and make some extra if this is your first time.
- Mushroom. We used Cremini (or Baby Bellas) for this recipe, but any mushroom would work including the white buttons found at any supermarket. If you really want to raise the bar for this burger, try some Shiitake, Oyster, or Chanterelles – all of them are umami bombs that elevate this burger to the next level.
- Swiss Cheese. We just used pre-sliced deli swiss cheese which made preparation easy. If you really love this ingredient though, buying some Emmenthaler or Gruyère can only enhance the flavors of the onions and mushrooms.
How to Make Caramelized Onion Mushroom Swiss Turkey Burger
Here are the quick step-by-step instructions with visuals. You can find the full instructions with the exact ingredients will be in the recipe card below.
Pro-tip: Caramelized onions can be made in advance and frozen for future use so make a big batch and then freeze it in a freezer-safe container.
1. Caramelize the Onions: Roughly chop the onions so that slices are between ⅛ and ¼ inches thick. Heat the butter and olive oil in a saucepan on medium heat. Once the butter has melted, add onions and sweat them until they become translucent. Reduce heat to low and continue to cook onions, stirring every 5-10 minutes to prevent them from sticking. Deglaze the pan with a tablespoon or two of water or chicken stock when fond starts to form on the pan. As onions continue to caramelize, continue stirring every 5-10 minutes and deglazing the saucepan as fond forms and the onions are no longer loose in the pan. When the onions achieve a deep golden brown (or dark brown) remove them from heat and set aside.
2. Saute the Mushrooms: In a cast-iron skillet over medium heat, heat the olive oil and butter. Add mushrooms and saute until they have released their water, approximately 2-3 minutes. Remove mushrooms from skillet and set aside.
3. Prepare the Burger Patties: In a large bowl mix together ground turkey with Worcestershire sauce, kosher salt, black pepper, panko breadcrumbs, garlic salt, onion powder, and chopped fresh parsley. Divide the turkey mixture into three equal portions and form them into patties. Place patties on a small baking sheet and refrigerate for 10-15 minutes. Note: This step can be done in advance just keep the burger patties refrigerated until ready to cook.
4. Cook the burger: In the same cast-iron skillet used to sautee the mushrooms, cook turkey patties for approximately 3-5 minutes per side then cover with a lid to help cook the center all the way through. When burgers have reached an internal temperature of 165 degrees top with cheese and cover until cheese has melted.
5. Plate: Serve burgers on a toasted bun and top with sauteed mushrooms and caramelized onions. Add additional toppings if desired.
Recipe Pro-Tips and Notes
- Use a preheated cast-iron or nonstick skillet to get a browned seared exterior.
- Turkey burgers can also be grilled on an outside gas or charcoal grill for added flavor.
- Turkey burgers need to be cooked to an internal temperature of 165 degrees. Above 165 degrees and burgers will begin to dry out.
- To bind the patties together use breadcrumbs. It will also help the patties keep their shape.
- Turkey burgers are best served immediately when they are still juicy.
Make-Ahead and Freezing Instructions
To Make Ahead: Make the turkey burgers through step 2 of the recipe, prior to cooking. Place them on a baking sheet and cover them with plastic wrap. Refrigerate up to one day prior to cooking.
To Freeze Ahead: Make the turkey burgers through step 2 of the recipe, prior to cooking. Place burgers on a parchment-lined baking sheet and put them in the freezer for one hour. Once the patties have partially frozen, layer them between parchment paper in a freezer bag or freezer-safe container. Freeze burgers for up to 3 months. To cook, thaw burgers overnight in the refrigerator and then cook as recommended in step 3 of the recipe.
Frequently Asked Questions
Turkey burgers need to be cooked to an internal temperature of 165 degrees. To get the juiciest burger avoid cooking them past 165 degrees.
You can prevent them from falling apart by adding a filler such as breadcrumbs. We like using panko for our burgers but you can also use crushed crackers or an egg. Turkey patties should also be made thicker than your traditional beef patty so opt for a patty that is 3/4 – 1 inch thick. This will help them from falling apart as you flip them.
Let’s Connect! If you make our Caramelized Onion Mushroom Swiss Turkey Burger or any other recipe on Casual Epicure, please don’t forget to rate the recipe and leave a comment below. It helps others who are considering making our recipes and we love hearing about your cooking experiences. And if you snapped some shots, share them on Instagram, and be sure to tag @casual.epicure so we can feature them in our stories.
Other Recipes to Try
If you enjoy this recipe, we recommend checking out some of these:
Caramelized Onion Mushroom Swiss Turkey Burger
Equipment
- 1 10-12 inch Cast-Iron Skillet (Large)
- 1 Medium Saucepan with High Sides
Ingredients
Caramelized Onions
- 1 large sweet or yellow onion, peeled
- ¾ tablespoon olive oil
- ¾ tablespoon unsalted butter
- ½ cup water or chicken stock
Sauteed Mushrooms
- 2 tablespoons olive oil
- 6 ounces mushrooms, stemmed and sliced
- ½ teaspoon unsalted butter
Burger
- 16 ounces ground turkey, 85% lean
- 1 tablespoon Worcestershire sauce
- ½ teaspoon kosher salt
- ½ teaspoon black pepper
- ¼ cup panko breadcrumbs
- ½ teaspoon garlic salt
- 1 teaspoon onion powder
- 3 tablespoons chopped parsley
- 4 slices Swiss cheese
- 4 hamburger buns
Instructions
Caramelized Onions
- Rough chop onions so that slices are between ⅛ and ¼ inches thick.
- Heat the butter and olive oil in a saucepan on medium heat. Once the butter has melted, add onions and sweat them until they become translucent.
- Reduce heat to low and continue to cook onions, stirring every 5-10 minutes to prevent them from sticking. Deglaze pan with a tablespoon or two of water or chicken stock when fond starts to form on the pan.
- As onions continue to caramelize, continue stirring every 5-10 minutes and deglazing the saucepan as fond forms and the onions are no longer loose in the pan.
- When the onions achieve a deep golden-brown (or dark brown) remove from heat and set aside.
Sauteed Mushrooms
- In a cast-iron skillet, heat olive oil and butter over medium heat.Â
- Add mushrooms and saute until they have released their water, approximately 2-3 minutes. Remove mushrooms from skillet and set aside.
Burger
- Combine ground turkey with Worcestershire sauce, kosher salt, black pepper, breadcrumbs, garlic salt, onion powder, and chopped parsley.
- Divide the turkey mixture into three equal portions and form them into patties. Place patties on a small baking sheet and refrigerate for 10-15 minutes.
- In the same cast-iron skillet used to sautee the mushrooms, cook turkey patties for approximately 3-5 minutes on each side. When burgers have reached an internal temperature of 165 degrees top with cheese and cover until cheese has melted.
- Serve burgers on a toasted bun and top with sauteed mushrooms and caramelized onions. Add additional toppings if desired.