Steak Bites with Onions and Mushrooms

Delicious and juicy seared steak, meaty mushrooms and sweet onions, that is what this dish delivers every time! My family craves this recipe when we are camping, it’s quick to make which means I don’t have hangry campers asking when is dinner and you won’t either.

You can choose any cut of beef that you like, for the recipe I choose strip steak, my grocery store had a special on it. But from time to time I used, Ribeye, top sirloin, and NY Strip successfully.

Cut the steak into 1.5 inch pieces.  If they are any smaller the steak will cook too fast, if they are larger than 1.5 inches the cook time will be longer. Bite size is the way to go for a faster cook time.

Slice the mushrooms all the same size, again by doing this they will not only cook evenly but they will develop a beautiful deep brown color from the hot pan.

Wait to prep the onion until the day you are making this dish. As you know onions have a very strong smell and your RV, ice chest, or home fridge will be perfumed with their strong scent. Best to hold off.

Allow your cast iron pan enough time to pre heat before you start cooking. This can take about 10 minutes, the perfect amount of time for yo to gather all your ingredients you have prepped ahead of time.

Next, we need to assemble the marinade.  Good news you can make this well in advance! I have made and stored this flavorful marinade three days before I used it, another time saver when you are camping.

Steak Bites with Onions and Mushrooms
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  • 2 pounds strip steak (or other grilling steak) cut into 1-inch cubes
  • 8 ounces whole mushrooms (cremini, or bella)
  • 1 large yellow onion, sliced
  • ½ cup balsamic vinegar
  • ¼ cup Worcestershire sauce
  • ¼ cup olive oil
  • 2 tablespoons soy sauce
  • 2 tablespoons light brown sugar
  • 1 tablespoon Dijon mustard
  • 3 garlic cloves, minced
  • 2 teaspoons fresh parsley, chopped
  • 1 teaspoon fresh chives, chopped
  • ½ teaspoon ground black pepper
  • ¼ teaspoon red chili flake


  1. In a medium size bowl, whisk together balsamic vinegar, Worcestershire, olive oil, soy sauce, brown sugar, mustard, garlic, parsley, chives, black pepper and chili flake. Reserve ¼ cup of the marinade, place in a smaller bowl cover and place in the refrigerator.
  2. In a large zip top plastic bag, place steak pieces inside and pour marinade over the beef, seal the bag closed. Place in the refrigerator 4 hours or overnight
  3. Preheat griddle to medium high heat. Remove beef from marinade and place on a sheet pan or plate while griddle is coming to temperature.
  4. Quarter mushrooms and place in a bowl, slice onion and place in the bowl with the mushrooms, pour reserved marinade over mushrooms and onions, toss well, set aside.
  5. Pour 2 tablespoons of grape seed oil in the hot griddle, spread with a spatula or heat resistant basting brush. Cook beef for 8-10 minutes, turning often, until seared and caramelized, you are looking for an internal temperature of 130-135 degrees for medium rare/ medium. Remove and set aside on a platter to rest covered loosely with foil for 10 minutes.
  6. Pour 2 tablespoons grape seed oil on the griddle; add the mushrooms, onions and marinade. With your spatula quickly and carefully sauté the vegetables until they are caramelized, about 10 minutes, turn off heat source and place cooked vegetables on the platter with the steaks. Serve while warm.