Four Cheese Mushroom Toasts 

Sometimes you want something quick, easy, and filling. And, sometimes, you want something that is all of those things, as well as cheesy, messy, and loaded with carbs. Four Cheese Mushroom Toasts is just what you need! It’s one of those great weeknight dinners that just makes you feel all warm and cozy!

Originally published here at Lord Byron’s Kitchen back in June 2015, I thought it was time to give this recipe a facelift. I have not changed the recipe at all, however, I have updated the instructions so that you at home can get perfect results every time you make these Four Cheese Mushroom Toasts. I have also updated the photographs because the original photographs were ew!

Back then, toasts were all the rage. They were everywhere! I think it all started with the popularity of smashed avocado toast. Soon after that, we all turned toast into these beautiful creations with lots of toppings and of course, cheese too! This is exactly how it started for me.

TOPPED TOAST POPULARITY

It’s no big secret that I used to have a full-on love affair with The Pioneer Woman.  I used to watch the show every chance I got.  On one particular episode, Ree dedicated a whole segment to the popularity of toasts.  She also agreed that toast topped with various ingredients had become rather popular, not only for the home cook but on many restaurant menus and especially food trucks. 

I guess the appeal is that they are easy to prepare, extremely easy on the wallet, and completely filling.  I, for one, can make a complete meal on bread!  Additionally, with toasts, each individual taste can be satisfied. But, being that I am on a mushroom kick, lately, I wanted to try my hand at these toasts and see what I could come up with.  Little did I know that I would be piecing together the most delicious thing I’d ever put in my mouth.  I’m serious!

PERSONAL TASTE DOES CHANGE OVER TIME

Now, my ex-wife follows my blog.  She loves mushrooms.  We were together for 10 years and she endured 10 years of me bitching about mushrooms in her recipes.  She watched for 10 years as I picked mushrooms out of whatever she had prepared.  I recall how she loved to put mushrooms in spaghetti sauce and I would hoot and holler and howl all the way through dinner.  And, I’d love to say that she quietly sat by and said nothing, but that wasn’t the case, was it, my darling Tanya?  I know exactly what she’s going to say when she reads this; it will go something like this: “What a contrary bitch! Now he likes mushrooms!”

You see, I have found, after 39 46 years on this earth, that I love mushrooms as long as they are cooked my way.  Oh, and I will only eat cremini mushrooms. Cremini mushrooms are meaty and unlike other mushroom varieties that I’ve tried, they don’t have a slightly slimy texture.  Cremini mushrooms are basically portobello mushrooms which are harvested before the cap has opened. 

When I prepare mushrooms, I like to sauté them in a little butter and olive oil until they are a deep brown colour and have shrunk tremendously in size.  Personally, I feel this adds to the meat-like consistency because the cooking process releases moisture and allows the mushroom to reduce in size and take on a meatier texture and flavour.

INGREDIENTS NEEDED TO PREPARE THIS RECIPE

The following is a list of the ingredients needed to prepare this recipe. For exact amounts and measurements, refer to the printable recipe card located near the bottom of this post. 

• Bread – If serving these as a meal, use a substantial bread like sourdough. But, for an appetizer size, use a baguette sliced on a diagonal.
• Mushrooms – Use good meaty mushrooms like cremini.
• Salted Butter – You can use unsalted butter too. Just be sure to taste the mushrooms and add more salt if needed. Butter is used to cook the mushrooms and also in the cheese spread mixture.
• Worcestershire Sauce – This adds so much flavour to mushrooms!
• Ground Black Pepper
• Olive Oil – Just a little bit of olive oil is needed. Since it has a higher smoking point, it will prevent the butter from burning.
• Mayonnaise – You can use any mayonnaise, even the fat-free stuff!
• Sour Cream – These toasts are indulgent – let’s face it! Use full-fat sour cream since fat-free sour cream is runnier. Thicker is better here.
• Garlic – Use fresh garlic and mince it really finely.
• Dehydrated Onion Flakes – I used these because I knew that fresh onion would add water content. Onion flakes will soak up moisture content. It was an easy win!
• Cheese – These are Four Cheese Mushroom Toasts, so four different cheeses are used. You can change up the cheese based on your preference. The only caveat is that they are good melting cheeses. Parmesan is a must, but the others can vary. I like to use Swiss, mozzarella, and havarti.
• Green Onions – These add freshness, colour, and lots of flavour.

FRESH MUSHROOMS MAKE ALL THE DIFFERENCE

It took me years to figure out that I actually did like mushrooms, and that I had been brainwashed into thinking that mushrooms were these pale, brown, slimy, button-looking things that came out of a can. Once I began to experiment with fresh mushrooms, my opinion of them changed rather quickly.

My mom can’t be blamed for not using fresh mushrooms. I grew up in Newfoundland, and I know that canned mushrooms were all my parents could purchase at the time. I remember it well – there were sliced mushrooms, or if you were being very frugal, you could get stems and pieces in a can too.

Mom would often fry canned mushrooms with chopped onion together in her cast iron skillet. It would just be those two ingredients with a little butter, some salt, and ground black pepper. She would spoon it over the top of fried or grilled steak or pork chops. It looked so good, but I wouldn’t even try it. Fresh makes all the difference, because now I like mushrooms.

HOW TO MAKE FOUR CHEESE MUSHROOM TOASTS

1. Browning the Mushrooms

Here is how this all went down back in 2025. I arrived home from work and started to think about dinner. Because of that episode of The Pioneer Woman, the idea of combining sautéed mushrooms with toast was all I could think of.  I got to work sautéing the mushrooms in some salted butter and olive oil with a little black pepper and salt.  I cooked them until they turned a deep, woodsy, brown colour.

You have the option of frying the mushrooms to your liking. You may not want your mushrooms to be so well done. However, if you choose to fry them less than I have, please be warned that the extra moisture content in the mushrooms will seep. What this means is that the water content left in the mushrooms will leak out into the cheese spread mixture, which will thin it. Depending on how much moisture is released, the toast may end up being soggy.

Once the mushrooms are cooked, remove them from the skillet and transfer them to a plate. Spread them out so that they will cool quickly. You do not want to mix the cheese spread mixture with hot mushrooms. The cheese will begin to melt before it gets to the oven. Once cooled, sort through the cooked mushrooms and separate the broken and smaller bits from the whole slices.  The nice pieces should be saved for topping the toasts while the rest will be incorporated into the cheese mixture later.

2. Preparing the Cheese Spread

To make the cheese spread, it is as simple as mixing the ingredients together in a mixing bowl. Add the mayonnaise, sour cream, and melted butter to the bowl first. Whisk those together until combined. Next, add in the garlic, onion flakes, and black pepper. Stir those into the mayonnaise and sour cream mixture. Finally, add the four cheeses and the green onions. Fold those into the cheese until evenly dispersed throughout the mayo and sour cream. Set that aside until you’re ready to assemble the toasts.

3. Preparing the Toasts

Bread. Oh, how I love bread! For these Four Cheese Mushroom Toasts, you will want to use what I call substantial bread. I prepared these toasts as a meal, so I used larger slices, but you can certainly use a baguette if you are planning to use these toasts as an appetizer.  Sourdough is a great choice too!

Place the bread in a single layer onto a large sheet pan. Put it under the broiler until lightly browned. Remove the bread from the oven and flip it over. Toast the second side as well.  Now, allow the bread to cool slightly so that the slices are just warm to the touch. Spread the cheese mixture onto each toast.  I used the spread rather generously. The sourdough in the photographs here is about seven inches long. The cheese mixture made four slices.

Top the toasts with the remaining nice mushroom slices that you reserved earlier. Place the sheet pan back in the oven and carefully watch while the cheese began to bubble and brown.  Don’t burn the toasts, obviously, but keep them under the broiler until you are satisfied with the colour.  You will also want to make sure the cheeses are melted all the way through if you decide to be generous with the spread as I did. All in all, it will take about 3-5 minutes until a 500 degrees F broiler.

NEED MORE OR LESS?

Lastly, you can double this recipe depending on how many toasts you need to prepare.  For that matter, you can also halve the ingredient amounts if you need less. As listed now, the ingredients will make 4 large toasts or about 10-12 baguette slices.

That’s about as easy as it gets!  In my humble opinion, you’ve got a complete meal on your hands.  Of course, you can serve these up any which way you like.  They might be good served with a mushroom soup or even a small portion of pasta.  I also like to serve them with a side of kettle chips. Either way, these toasts will be the highlight of your meal.  Trust the guy who ate two of these even though he doesn’t like mushrooms!