Best Onion Mushroom Burger

by Dorothy Reinhold on July 17, 2012

Print This Post Print This Post Best Onion Mushroom Burger

Don’t you hate it when the topping falls off the hamburger? What if you put the sautéed mushrooms and onions INSIDE the burger instead of piling them on top after it is cooked?

Mushrooms in the skillet on

Mushrooms go into the skillet. They will saute and sweat.

Kitchen epiphanies can happen anytime, and this one struck as I was throwing the sliced mushrooms into the skillet for what I hoped would be a classic burger topping. After they were cooked down and the onions getting caramelized, I thought, “Who said I couldn’t just mix them into the raw meat?”

Onions and mushrooms in the skillet on

Onions join mushrooms. I most often use red onion, but here I used yellow onion.

Ring a ding ding!

Onions and mushrooms on

Sauteed mushrooms and onions are ready for their chop. Nice steam!

The most perfect onion mushroom hamburger!

Best Onion Mushroom Burgers on

Mix gently and form into patties. The vegetable mixture “stretches” the meat farther.

Recipe: Best Onion Mushroom Burgers

Summary: Why not stuff the sautéed mushrooms and onions inside the burger so they don’t slide off? This creates the best, most flavorful hamburger that won’t even need condiments!


  • 1 tablespoon olive oil
  • 1 pound sliced mushrooms
  • 1/2 cup finely diced red onion (or yellow onion)
  • 2 garlic cloves, crushed
  • Kosher salt (big pinch ~1/2 teaspoon)
  • Black pepper (a few grinds)
  • Big pinch Italian herb blend, or finely minced fresh rosemary
  • 1 pound ground beef (10% or 15% fat preferred), or use ground bison
  • 1 tablespoons bacon grease (or use olive oil)
  • 4 or 5 King’s Hawaiian Sweet Sandwich Buns
  • 2 tomatoes, sliced
  • Fresh spinach or lettuce leaves


  1. In a large skillet over medium heat, add oil and sauté mushrooms and onions. Stir several times; they will take about 10 minutes total to cook. Add garlic, salt, pepper and herbs during last 2 minutes of cooking time.
  2. Remove pan from heat and scrape vegetable mixture onto a cutting board. Using a large knife, chop mushroom-onion mixture finely; it will be steaming hot. Scrape it into a mixing bowl. Add ground beef to mixing bowl and mix gently but thoroughly (I use the KitchenAid mixer for this, on low). Form mixture into 4 or 5 patties.
  3. In same skillet, heat bacon grease. When hot, add patties. Fry until done, about 3-4 minutes on each side.
  4. Assemble burgers on bun with tomato slices and spinach leaves on each burger, topped by the bun lid. You may find, as we do, that you won’t need any extra condiments because these patties are packed with flavor.
  5. Serves 4-5.

Quick notes

You may use whatever bun you like. If left to my own devices, I favor an onion bun, but these King’s Hawaiian Sandwich Buns are also great with so many burgers, and very kid-friendly. The mushroom-onion mixture “stretches” the meat to make an extra patty. If you have hearty eaters, make 4 large patties.

Preparation time: 20 minutes
Cooking time: 8 minutes
Number of servings (yield): 4-5
Culinary tradition: USA (General)
My rating 5 stars:  ★★★★★ 

Best Onion Mushroom Burger on

Impromptu sides of sliced fresh mango and homemade applesauce!

{ 7 comments… read them below or add one }

Irene Handiyanto Petersen July 4, 2013 at 9:09 am

I tried your recipe and it was delicious! I added 1/4 cup of bread crumb though, to keep the burger extra moist. Thanks for sharing, tonight i’ll try your hatch chili recipe 🙂


Mama's Gotta Bake July 21, 2012 at 10:32 am

Hi Dorothy, having a family BBQ tomorrow and we’re going to give your Best Onion Mushroom Burgers a try! I’ve never considered putting the toppings in with the meat, but it sounds like a darn good idea!


Dorothy July 21, 2012 at 12:40 pm

So glad you are trying it! Let me know if you like it!


Asiya July 17, 2012 at 1:19 pm

That is a fantastic idea! I hate it when I’m eating a burger and things start to slide out.


Connie Kaiser July 17, 2012 at 7:53 am

What a terrific idea! I was searching for a new burger twist!!!!


Leave a Comment

Previous post:

Next post: