Portobello mushroom buns are a great, veggie-filled replacement to hamburger buns. We used grilled halloumi, avocado and tomato for the filling in this keto vegetarian recipe.
The portobello mushrooms caps are grilled and used as a burger bun and have a great flavor and tasty textures. This is a recipe which can be adapted to your own taste and filled with any keto vegetarian or vegan burger.
We have a keto mushroom burger recipe made out of Portobello mushrooms, so why not use this large mushroom in place of a burger bun for a keto vegan option?
Jump to:
CARBS IN PORTOBELLO MUSHROOMS
Mushrooms are a low carb vegetable and vary slightly between varieties. Portobello mushroom caps are just 4g net carbohydrate per 100g serving. The average weight of a portobello mushroom is 3 ounces/85 grams.
MUSHROOM HALLOUMI BURGER INGREDIENTS
This is an easy recipe and a portobello burger bun is just a couple of mushrooms! For this recipe we are showing the ingredients for our delicious mushroom halloumi burger.
- Portobello mushrooms - Select firm portobello mushrooms that are similar in size.
- Halloumi cheese - Grilled slices of halloumi make a great vegetable burger option.
- Avocado - Slices of ripe avocado go well with both the mushroom and the halloumi
- Tomato - We like a slice or two of tomato with our vegetarian burgers!
- Lettuce - For the colour and the crunch
- Everything Seasoning - An optional topping for the top of the mushroom burger bun.
- Avocado oil - This can be replaced with olive oil.
HOW TO MAKE PORTABELLO MUSHROOM BURGER BUN
Prepare the portobello mushrooms by cleaning them with a damp cloth to remove any dirt, then removing the stems. The stems could be used in a mushroom stock recipe so don't be too hasty to throw them out.
Cooking the portobello mushrooms is as simple as brushing them with avocado oil then grilling then on the BBQ or a grill pan. After then it's all about the assembly!
We added Everything Seasoning to the top mushroom burger bun but this is entirely optional. Sesame seeds could be used or just leave it plain with grilled lines.
Place the least pretty of the grilled mushrooms at the bottom
Layer the lettuce and sliced tomatoes on top of the grilled mushroom
Add the grilled halloumi and slices of avocado
Top with the remaining portobello mushroom and sprinkle the seasoning on top.
WHAT TO SERVE IN A MUSHROOM BUN
You can use any keto vegetarian or vegan burger option in a mushroom bun. We would recommend a filling that pairs with the strong mushroom flavor of the portobello though.
Grilled halloumi cheese makes an excellent option as the cheese holds its shape when grilling and the salty flavor goes well with the mushroom.
A few other options to try are:
- A low carb meat free burger patties - We like the Morning Star brand but always check the nutritional information for the carbohydrates and ingredients.
- Slices of grilled Feta - Another firm cheese that grills well and is great with mushrooms.
- Grilled vegetables - Use layers of chargrilled red peppers and zucchini for the filling for a vegan Mediterranean flavor.
- Mozzarella cheese, basil and slices of beet tomatoes - Caprese flavours in a burger
- Lupini Bean Patties - A low carb vegan burger option
SIDES WITH A KETO PORTOBELLO MUSHROOM BURGER
This is a hearty dish by itself when filled with grilled halloumi and vegetables but you could serve this with a few low carb sides.
MORE KETO PORTOBELLO MUSHROOM RECIPES
If you are a fan of portobello mushrooms we have a few low carb recipes you may enjoy.
Spinach Feta Stuffed Mushrooms
This post may contain affiliate links. Please read my disclosure policy for more information.
Portobello Mushroom Burger Bun
Ingredients
- 2 medium portobello mushrooms
- 4 oz Halloumi cheese
- ½ medium tomato
- 1 leaf lettuce
- ½ avocado
- 1 tablespoon avocado oil
- 1 teaspoon everything seasoning optional
Instructions
- Brush the portobello mushroom caps on both sides with the avocado oil. Grill on a medium-high heat on the BBQ or griddle pan on both sides for about 5 minutes each side.
- Slice the halloumi cheese in half lengthways. Grill on the BBQ or griddle pan until golden.
Assemble
- Place the less pretty mushroom cap (trust me, there's always one!) on a plate.
- Layer the lettuce leaf, then tomato slices, halloumi and avocado. Top with the remaining portobello mushroom cap. Sprinkle the Everything Seasoning (optional)
- Serve immediately
Notes
YOUR OWN NOTES
Nutrition
