Portobello Mushroom Sandwich – Do you love a great sloppy-joe but want to lighten up your meal? This Portobello Mushroom Sandwich is the easiest and most delicious sandwich. Cooked in the slow cooker or Instant Pot (works for either!) It takes ten minutes in prep and it’s hands off after that.
No one will miss the meat with this big meaty Portobello Mushroom Sandwich!
This vegetarian meal was inspired by our visit to Hawaii a couple years ago. This is a blog I released two years ago. As I was updating the recipe and pictures, I realized many of the pictures are worth sharing again, so enjoy!
We made a trip over to Hawaii to see the kids. As always, a trip to the Islands is such a treat and this time it was even sweeter because we went to see our Grandchild Baby Juna!
Juna & I – here she’s about 10 weeks old!
Juna was just 10 weeks old and a sweet bundle of joy! I got to hold her and cuddle her….such a sweetie pie!
Ingrid watches carefully over Juna while I babysit!
Above is my favorite picture I took, it hangs above my desk in my office. Our Granddog Ingrid was very concerned when Mommy left and had to make sure I did everything just right! It was a precious moment. 
And there were a few more fun ones…. I mean Juna was born in Hawaii so she obviously needs a hula skirt…right? My friend Gina made this for her and it turned out super cute!!! Dan and I decided Juna should call us Grandma & Grandpa Tutu. (Tutu is Hawaiian for Grandma/Grandpa.) Ok….am I being the doting Grandmother? 😀 Needless to say, Juna has our hearts!
I did promise you a recipe today and that recipe is for a delicious Portobello Mushroom Sandwich. This sandwich was inspired by our visit to Hawaii. When we are there, we often stay in Waimanalo which is on the eastern side of Oahu. It’s the most picturesque beach I’ve ever seen.
Waimanalo Beach
Miles of gorgeous beach. We usually have the beach to ourselves! Absolutely breathtaking beauty!
In the city of Waimanalo there is a tiny little five star vegan restaurant. Here we discovered the most amazing food! ‘Ai Love Nalo keeps sparse hours and always has a line out the door. The food is spectacular! This blog was first released two years ago. Since then every time we visit Hawaii, we dine at this restaurant.
We enjoyed a couple of meals there and a favorite is the Mushroom Burger – hands down the most fantastic burger (beef, chicken or vegan) that I’ve ever eaten. I’ve done my best since we came home to replicate that burger!
Portobello Mushroom Sandwich
And I might add…I’ve came pretty close (Dan says it’s better!) ! This burger is slow cooked with mushrooms, red onions and bell peppers. I’ve tried making my own bbq sauce and also using my favorite store bought sauce and you know what? Either way it’s equally as delicious so why not make it easy on yourself and just use store bought?
This meal can be made in the slow cooker or Instant Pot. While it is cooking make the coleslaw and toast your burger buns. That’s it!
When you plate the Portobello Mushroom Sandwich, position the mushroom stem side up. It creates a bowl to hold the sliced mushrooms, peppers and onions.
Portobello Mushroom Sandwich – Shopping List
- portobello Mushrooms
- sliced Mushrooms
- red onion
- red bell pepper
- bbq sauce
- fixings for coleslaw (or pre-made from the Deli department)
Here are the steps!
Here are the steps –
- clean the mushrooms, put them in the slow cooker
- add the sliced peppers and onions
- top with bbq sauce and spice. Stir to combine.
- toast the burger buns because this is an oozy-gooey burger and toasting the bun keeps it from getting soggy.
Now that burger we had at ‘Ai Love Nalo was pretty fabulous and I have to say, I’ve worked to make this recipe comparable and my hubby say I nailed it! 
When you assemble the burger, place the portobello on the bun first stem side up. Placing it with the stem side up creates a natural bowl for the sliced mushrooms, peppers and onions and keeps them from sliding off – then top it off with a big dollop of cole slaw!
Top each sandwich with a dollop of coleslaw.
Portobello Mushroom Sandwich – Tips
- toast or grill the bread (keeps it from getting soggy)
- remove the gills from the portobello mushrooms
- place the portobello mushroom on the bun first, stem side up – this creates a natural bowl for the sliced mushrooms, peppers and onion
- can be made in the instant pot
Read about more of our adventures here – Family Fun Night with the Oakland A’s and our visit to Mesa Verde National Park
Portobello mushrooms give it that big steak flavor and making it in your slow cooker is super easy. This Portobello Mushroom Sandwich is big, meaty, hearty and most of all delicious!
If you love this recipe as much as I do, please be sure to rate it below! It is You have to give this amazing burger a try and please let me know what you think
Portobello Mushroom Sandwich
Ingredients
- 2 portobello mushrooms
- 1 16 oz package pre-sliced mushroom
- 1 red bell pepper
- 1/2 red onion
- 1/2 cup bbq sauce - use your favorite
- 1 teaspoon salt
- 1/2 teaspoon pepper
- healthy pinch red pepper flakes
- Coleslaw
- 1/2 head cabbage
- 2 carrots
- 1/2 red onion
- 1/2 cup mayonnaise
- 2 tablespoons cider vinegar
- 2 tablespoons honey
- salt and pepper to taste
Instructions
- Clean the portobello mushrooms, remove the stem & fins, place in the slow cooker. Top with the pre-sliced mushrooms.
- Slice the bell pepper, remove the seeds and slice into strips. Remove the outer peel from the onion and slice into strips. Place into the slow cooker with the mushrooms.
- Season the vegetables with salt, pepper & red pepper flakes, top with bbq sauce. Put the lid on the slow cooker & cook on high for 4 hours or low for 6.
- While the meal is cooking, make the cole slow. Thinly slice the cabbage, clean & shred the carrots (I use a box grater.), thinly slice the onions, place in a large bowl.
- Mix the coleslaw dressing together - it will be quite thick, but that's how you want it. Mix the dressing with the vegetables, refrigerate until ready to use.
- Toast the burger buns.
- Assemble and enjoy!
Nutrition
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Ok…maybe just ONE more picture of Juna with her proud Grandpa! 😀
Portobello Mushroom Sandwich is a big meaty (vegetarian) bite!
