Portobello Mushroom Sandwich

These Portobello Mushroom Sandwiches are juicy, loaded with flavour and so easy to make!

Mushrooms are one of those ingredients that need some TLC to bring out the best in them. A bland mushroom is terrible, but a mushroom treated right is SO GOOD. Here we’re going to be whipping up the most delicious sandwiches, whilst keeping the mushroom the star of the show. Follow me…

Garlic Butter Portobello Mushrooms

There’s a few different ways you can prepare portobello mushrooms, but today we’re slathering them in a simple garlic butter then baking them in the oven.

Preparing Portobello Mushrooms

The only thing you really need to do is remove the dirt. To do this just grab a damp cloth a wipe them. Do not wash them. Mushrooms already contain a huge amount of water so we don’t want to add to that. You also don’t need to gut them or remove the stalk, keep all that goodness!

Garlic Butter

For the garlic butter all you need is melted butter, garlic, parsley, salt and pepper. At it’s bare bones though you don’t need parsley, I just like it as it’s a classic pairing with garlic butter and adds another layer of flavour.

Can I use other Mushrooms for this recipe?

You really want mushrooms the size and shape of a Portobello. In the UK we have large flat mushrooms, which work nicely. You’re looking for around 3.5oz/100g per mushroom – so pretty big!

Process shots: melt butter (photo 1), add parsley, garlic, salt and pepper (photo 2), brush mushrooms (photo 3), bake (photo 4).

Portobello Mushroom Sandwich

I tested a few different combos/fillings for this sandwich, and settled on this:

• Hummus – This adds a really nice creamy, nutty flavour to the sandwich and pairs perfectly with the mushroom.
• Caramelized Onions – If you’re short on time or prefer the sharper flavour of raw onion, then just add sliced red onion.
• Roasted Red Peppers – Store bought or homemade (more on this in the recipe card). If you don’t like peppers then sub tomato.
• Greens – I use a combo of spinach and rocket, but add any salad leaves you fancy. Watercress also works nicely.

What Bread to use?

I highly recommend using ciabatta. It crisps up beautifully and creates a nice contrast to the soft mushroom/fillings. You could sub other types of rolls, just make sure you toast them.

Process shots: toast bread (photo 1), spread hummus (photo 2), add onions (photo 3), add mushroom (photo 4), add greens and pepper (photo 5), add bread (photo 6)

Serving Portobello Sandwiches

You’ll want to eat these right away, just so the mushroom stays warm. You don’t want to make these ahead of time because a) cold mushrooms aren’t great and b) the butter will firm up again and congeal around the mushroom.

You can serve the sandwiches whole, or slice in half and enjoy that way!

• Crisp/Chip Recommendation: I love a Roast Chicken flavour with this sandwich (because chicken and mushroom is the best combo).
• Side Recommendation: Add some Sweet Potato Wedges or serve with a Roasted Veggie Salad!

For more mushroom goodness check out my Mushroom Grilled Cheese!

Alrighty, let’s tuck into the full recipe for this Portobello Mushroom Sandwich shall we?!

How to make a Portobello Mushroom Sandwich (Full Recipe & Video)

Portobello Mushroom Sandwich

These Portobello Mushroom Sandwiches are juicy, loaded with flavour and so easy to make!

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Course: Dinner, lunch

Cuisine: Universal

Prep Time: 10 minutes minutes

Cook Time: 25 minutes minutes

Total Time: 35 minutes minutes

Servings (click & slide): 4 sandwiches

Calories per serving: 326kcal

Author: Chris

Cost per serving: £2.50 / $3

Equipment

• Large Baking Tray
• Small Pot (for garlic butter)
• Sharp Knife & Chopping Board
• Brush

Ingredients

Mushroom

• 4 large Portobello Mushrooms (can sub large flat mushrooms of similar size - approx 3.5oz/100g each)
• 4 tbsp / 2oz / 60g Unsalted Butter, melted
• 1 tbsp very finely diced Parsley
• 2 cloves of Garlic, very finely diced then mashed with the blade of your knife
• 1/2 tsp Salt
• 1/4 tsp Black Pepper

Sandwich

• 4 Ciabatta Rolls, halved & toasted (see notes)
• 4 heaped tbsp Hummus
• 1/3 cup Caramelized Onions (see notes)
• 2 large Roasted Red Peppers, sliced (see notes)
• 4 pinches of Spinach/Rocket or greens of choice

Instructions

• Garlic Butter: In a small pot combine melted butter with parsley, garlic, salt and pepper.
• Coat Mushrooms: Place mushrooms on a baking tray stalk side down. Brush them with garlic butter, then flip them over and brush the insides with the butter.
• Bake Mushrooms: Place in the oven at 220C/450F for 20-30mins, or until fork tender. Timings will depend on the size of the mushrooms so just be vigilant. Tip out moisture gathered in the mushrooms if there's excess.
• Sandwich: Spread hummus over the bottom half of the ciabatta. Add onions, then mushroom, followed by greens and roasted red peppers. Add the second half of the ciabatta, gently press down then enjoy!

Quick Demo

Notes

a) Ciabatta - This works great because it crisps up nicely and counteracts the soft mushroom and fillings. You can use any kind of burger bun or roll though. To toast them either add the halves to a scorching hot dry pan, or broil under the grill. Either way I highly recommend toasting the bread, just to add crispiness to the sandwich.

b) Caramelized Onions - Check out my Caramelized Onions recipe for guidance. If you're short on time just fry up some onion until golden. Alternatively you can add raw red onion if you want more of a pungent flavour.

c) Roasted Red Peppers - I use store-bought and just squeeze out the brine then pat dry with paper towels. However you can make your own, just char the peppers on a flame on the stove or place under the grill. Once charred all over and tender, place in a bowl with cling film over until cool enough to handle, then peel away the skin with most of the char. If you don't like peppers then sub tomato.

d) Calories - Per sandwich:

Your Private Notes:

Click here to add your own private notes or reminders about this recipe.

Nutrition:

Nutrition Facts

Portobello Mushroom Sandwich

Amount Per Serving

Calories 326 Calories from Fat 101

% Daily Value*

Fat 11.19g17%

Saturated Fat 5.411g34%

Polyunsaturated Fat 1.468g

Monounsaturated Fat 3.347g

Cholesterol 15mg5%

Sodium 657mg29%

Potassium 766mg22%

Carbohydrates 48.79g16%

Fiber 5.2g22%

Sugar 18.6g21%

Protein 10.69g21%

Vitamin A 1748IU35%

Vitamin C 80.7mg98%

Calcium 151mg15%

Iron 3.3mg18%

* Percent Daily Values are based on a 2000 calorie diet.

*Nutrition is based on the absence of salt unless stated as a measurement in the ingredients. Cost is worked out based on ingredients bought from UK supermarkets, then divided by the number of servings. In both instances these values are just for guidance. Please check out my FAQ Page for more info.

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