Caramelized Onions & Mushroom Chicken Sandwich

Caramelized Onions & Mushroom Chicken Sandwich

What started as a way to use leftover ingredients, turned out into a great onion & mushroom sandwich that we'd pack for lunch at work any day of the week.

Thanks to Aaron Casey of SmokeytireBBQ for sharing this recipe with the community! 

You Will Need

  • 2 Boneless Chicken Breasts
  • 2 Pieces of Black Forest Sliced Ham
  • 4 Slices of Colby Jack Cheese
  • 1 Medium Sweet (Vidalia) Onion
  • 8 oz Package of sliced Baby Mushrooms
  • 2 Hamburger Buns (Sesame Seeds Preferred)
  • 3 Tbsp Kosmo’s Q SPG Rub
  • 2 Tbsp Kosmo’s Q Dirty Bird Rub
  • 1 Tbsp Honey Mustard Sauce (choose your favorite brand or make your own) 
  • 1 Tbsp Worceshire Sauce
  • 1 Tbsp Low-sodium Soy Sauce
  • 1 Tbsp Balsamic Vinegar
  • 3 Tbsp Unsalted Butter
  • 2 Tbsp Canola Oil
  • Lettuce & Tomato (Optional)  

The Prep

To get this party started, fire up your grill! Prepare for indirect cooking, and let the temp climb up until it settles in the 350-400ºF (176-204ºC) range. 

In a 12-inch cast-iron skillet, heat up 1 tablespoon of canola oil and 1 tablespoon butter. While it's going, season each side of the chicken breasts with SPG and Dirty Bird (or use your own spice blend).

The Cook

Time to get cooking! Place the chicken breasts in the heated skillet, over direct heat. Brown each side, then add 1 more tablespoon of butter, and close the lid. Let it cook like this until its internal temperature hits 165ºF (74ºC).

Now move the skillet to the cooler (indirect) side of the cooker. Add honey mustard, sliced ham, and 2 slices of cheese for each breast. 

In a smaller skillet, on the hot side of the cooker, heat up 1 tablespoon canola oil and 1 tbsp butter. Slice up the onion and mushrooms, and throw them into the skillet. Season with SPG, and add Worcestershire, soy sauce, and balsamic vinegar. Let the sauce simmer, stirring occasionally until the onions and mushrooms caramelize.

The Payoff

Hungry yet? We're almost there. Only thing that's left to do is give the buns a toast directly on the grill, and assemble your sandwich! Stack some onions and mushrooms on top of the chicken breast. Add lettuce and tomato if you like!

And that's all there is to it - hope you enjoy your onion & mushroom sandwich. Again, thanks to Aaron Casey of SmokeytireBBQ for giving us the recipe!

Catch you on the next one!


Submit your own recipe. Embrace greatness.

Have you worked with Kosmos for a while, and come up with something even better? Many of our recipes are submitted by our wonderful customers, who come up with all sorts of ideas that we could never think of.

Go here to submit your own recipe. If accepted, you'll get 10% off the whole store.

Also in Recipes

America’s BEST Burger: Au Cheval-inspired Cheeseburger

People are calling this America's BEST Burger! Join us in recreating this Au Cheval-inspired cheeseburger recipe that will leave your friends and family begging for more.
Cherry Apple Cowboy Cut Chops

Looking for a quick & easy-to-follow pork chops recipe? These Cherry Apple Cowboy Cut Chops bring a mouthwatering combo of sweet and savory, no wonder we can't stop eating them!

Egg Salad Sandwich VS Pimento Cheese Sandwich

Egg Salad Sandwiches versus Pimento Cheese Sandwiches - today, we're solving this age-old debate once and for all. BIf you're craving a classic sandwich with a twist, look no further! 

Everyone wishes that they could have award-winning competition BBQ at their backyard barbecue parties. With Kosmo’s BBQ, that's exactly what you'll have, every time.