Portobello Mushroom Bun Burgers with Guacamole

Portobello Mushroom Bun Burgers with Guacamole is a delicious and veggie-packed bunless burger recipe. It’s topped with a perfect homemade guacamole.

Welcome to the second day of bunless burger week here at Primavera Kitchen, where I’m sharing 5 Low-Carb Bunless Burger Recipes. Today, it’s the Portobello Mushroom Bun Burgers recipe, and I’m sure you’ll enjoy it because this recipe is AMAZING!

The first recipe was this Spinach Sauce Bunless Burger that is to die for. The spinach sauce is so creamy with homemade mayo, spinach, and avocado. Yum! In this post, I also talked about how to know the safe internal temperature for your burgers. So if you have questions about that, you definitely should check it out. There’s also my Bunless Turkey Burger Recipe, Easiest Guacamole Recipe, and Easy Low-carb Bunless Burgers Recipe!

Before jumping to the recipe post, I would just like to ask you one thing. If you are re-creating one of these bunless burger recipes, don’t forget to use the hashtag #bunlessburgerweek on Instagram because I would love to see your bunless burger recipes too!

So, today I’m bringing you these Portobello Mushroom Bun Burgers with Guacamole that are simply a traditional hamburger using Portobello mushrooms as the bun. Cool, right? On top of that, these burgers are special because of the guacamole that adds much more flavor to this recipe.

How to clean Portobello mushrooms:

This is something very simple to do, but a very important step to have a delicious mushroom bun since they tend to come a bit dirty from the stores. You are just going to do a quick cleaning.

• First, you’re going to gently twist off the stem of each mushroom. The stem is delicious too, so I recommend saving it to sauté and add in your omelette or frittata for example.
• Then, hold the mushroom cap in one hand and use a spoon to scrape out all the gills from the underside of the Portobello mushroom cap. The gills, in my opinion, are not great to eat, so you can discard them. Now, they are ready to grill. Simple and easy!

How to grill a Portobello mushroom:

Now that your mushrooms are clean and ready to cook you need to marinate them before you grill them. Doing this first will make the mushroom buns much more flavorful.

• First, you will place all the ingredients for the Portobello Mushroom Buns in a small bowl and mix everything well to combine.
• Then, you will add the cleaned mushroom caps in the bowl and coat them with the olive oil mixture and let stand for 1 hour.
• Now, oil the grill or grill pan and bring the heat to medium.
• Add the Portobello to the grill and cook for 4 minutes or so. Using tongs, carefully flip the mushroom to the other side and grill for more 4 minutes.

How to shape the perfect burger patties:

Alright, here is a good way to shape your burger patties easily.

• First, divide your mixture of ground meat and spices into 6 equal amounts.
• Second, grease your hands with a little bit of olive oil. This will prevent the meat from sticking to your hands.
• Third, shape the burger patties into a ball using your hands and place them on a baking sheet lined with parchment paper.
• Finally, gently press each one until they get flat and 1 inch thick. Then, fix the edges with your hands since the side of the burger may crack or break apart. You’re all done and ready to grill.

Serve this burger with my Air Fryer Sweet Potato Fries or my Spicy Baked Sweet Potato Fries. 

4.34 from 3 votes

Portobello Mushroom Bun Burgers with Guacamole

Portobello Mushroom Bun Burgers with Guacamole is a delicious and veggie-packed bunless burger recipe. It's topped with a perfect homemade guacamole. 

© Author: Olivia Ribas

Prep: 15 minutes minutes

Cook: 10 minutes minutes

Total: 25 minutes minutes

Servings: 4 people

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Ingredients

For the Guacamole

• ▢ 1 avocado
• ▢ 1/3 cup red bell pepper finely chopped
• ▢ 2 tablespoons diced tomatoes
• ▢ ½ red onions chopped
• ▢ 1 garlic clove minced
• ▢ 1 tablespoon lime juice
• ▢ Salt and black pepper
• ▢ 1 tablespoon fresh cilantro chopped

For the Burger

• ▢ 1 lb ground beef
• ▢ 1 egg
• ▢ ¾ cup white onions chopped
• ▢ Salt and black pepper to taste
• ▢ ¼ teaspoon Dijon mustard or French's Yellow if you're doing Whole30
• ▢ 1 teaspoon garlic powder
• ▢ 2 teaspoons extra virgin olive oil

For the Portobello Mushroom Buns

• ▢ 2 tablespoons olive oil
• ▢ Salt and black pepper
• ▢ 1 garlic clove minced
• ▢ 8-12 Portobello Mushroom stems and gills removed

For Serving

• ▢ Slices of red onions tomatoes, cooked bacon and microgreen leaves or any other green leaves you prefer to serve.

US CustomaryMetric

Instructions

• Make the spinach sauce: Add avocado in a bowl and mash it with a fork. Add all the ingredients and stir well. Set aside.
• Place all the ingredients for the mushroom buns in a bowl, except for the mushrooms. Mix well. Add the mushroom into the olive oil mixture bowl and coat them well. Set aside for about 1 hour. Place “buns” on grill and let them cook for 4 minutes.
• To make the burger, combine all ingredients, except the olive oil, in a large bowl. Mix everything well to combine and using your hands divide the mixture into 4-6 burgers.
• Heat the olive oil in a non-stick grill pan (or simply cook your burger in a BBQ) over a medium-high heat. Cook the burger for 3-5 minutes on each side, or until reach 145°F for medium-rare or 160°F for well-done. Set them aside.
• To build each burger, top one Portobello mushroom guacamole, patty burger, more guacamole, two slices of red onions, 2 slices of bacon, 2 slices of tomatoes and some microgreen or leaves. Top with second Portobello mushroom ban.

Tips

• Do not overmix the meat, as it’ll lead to a dense and tough patty.
• Avoid squeezing the patties together tightly as you don’t want the patties to be dense.
• Make sure you don't rush the mushrooms as you want them to grill all the way through or the texture won't be as good.
• To store: Keep leftover burger patties in the fridge in an airtight container for up to 5 days. Store the mushrooms in a separate container. The guacamole also needs to be stored separately. The guac may brown over time.
• To reheat: Reheat the beef burgers on the grill or in the microwave.
• To freeze: Flash freeze the raw patties before transferring them to a freezer-safe bag and freeze for up to 3 months.

Nutrition Information

Serving: 1/6 Calories: 317kcal Carbohydrates: 14g Protein: 22g Fat: 18g Cholesterol: 73mg Sodium: 470mg Fiber: 5g Sugar: 8g

Nutrition information is calculated using an ingredient database and should be considered an estimate.