Mushroom Grilled Cheese the Perfect Comfort Food

When I think of a grill cheese sandwich I think of comfort food! I love a good grilled cheese sandwich, the crispiness of the warm bread and the yummy gooey cheese…oh so delish! But now, I thought I would put a little fun twist and make a mushroom grilled cheese sandwich to upgrade it to a more sophisticated version of the classic grilled cheese.

I’m using beautiful oyster mushrooms for this mushroom grilled cheese recipe.

oyster mushrooms

My husband loves mushrooms. I don’t know if you have noticed but I put mushrooms in a lot of my recipes just for him. I guess that’s love! I like mushrooms as well but am nowhere close to the fan of these fungi’s as my hubby is.

This sandwich is all my husband’s doing. Since he is such a fan of mushrooms, he came home after stopping at a farm in our town and surprised me with a huge box of oyster mushrooms. Since no one in the house it a major fan, you can just imagine my reaction to seeing a box full of exotic looking mushrooms.

But this caramelized onion and mushroom grilled cheese turned out amazing. I was so surprised how meaty these mushrooms tasted. If you like mushrooms even slightly you have to give oyster mushrooms a try.

oyster mushrooms, sliced red onions and cheese on a cutting board

If you are unfamiliar with oyster mushrooms, they naturally grow on or near trees. They have a delicate but meaty texture and are mild with a hint of Anise flavour. The mushrooms have a beautiful thin, oyster- or fan-shaped caps. I think out of all the mushrooms I have seen, these by far are the prettiest.

This recipe was very quick to put together and perfect for a weekday or a relaxed weekend. You can serve this sandwich with soup on the side or just eat the sandwich as is. That’s how we ate it and truly loved it.

Soup recipes you can try:

Easy Mexican soup with chicken

Simple and delicious cabbage soup

Curried butternut squash soup

What Ingredients Do I Need for the mushroom melt?

  • oyster mushrooms
  • red onion
  • butter
  • your choice of cheese – preferably something that will melt well like Havarti, Monterey Jack or Cheddar
  • crusty bread – I like Italian bread. You can also try sourdough and rye
2 loaves of Italian bread

Let’s Get Started

1. Wipe your oyster mushrooms with a damp paper towel to get rid of all the dirt. Oyster mushrooms grow on wood, so they shouldn’t be too dirty and don’t need much washing. If you do wash them, note that you want to give them a quick rinse and not keep them under water for too long as they will absorb lots of water and you will lose all the flavor.

2. Trim off the steam and roughly chop up the mushrooms – Discard the steams or save for use in a broth/stock.

3. Slice up the red onion.

4. Get your favorite cheese and slice it.

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5. In a large skillet, with 1 tbsp of butter over medium-high heat, sauté the onions and mushrooms. Sprinkle a little salt and pepper over the mushrooms while sautéing. Cook until mushrooms are tender and softened, around 5 to 8 minutes.

oyster mushrooms and sliced red onions in a frying pan

6. Transfer the mushrooms and onions onto a plate and set aside.

7. Add your buttered bread and grill it in the skillet on both sides

8. Add sliced cheese and mushrooms and top with another slice of grilled bread and continue grilling the sandwich until you can see that the cheese is melting.

9. Close up the sandwiches and cut in half. Enjoy!

Serving: 2 sandwiches

Prep Time: 5 minutes

Cook Time: 10 minutes


1 lb of oyster mushrooms

1 red onion sliced

½ tsp garlic powder

Salt/Pepper to taste

4 slices of cheese 4 slices of bread


1. Melt butter in a large skillet and sauté the sliced onion and mushrooms (5-8 minutes).

2. Season the mushrooms with salt, pepper and garlic powder.

3. Transfer the cooked mushrooms onto a plate and set aside.

4. Grill 4 slices bread on both sides.