Low-Carb Portabella Mushroom Tuna Melts Recipe

Mar 24 2023
We love to have fun with stuffed portabella mushrooms! (By that we mean we get creative with recipes… Not that we ride bikes together or take them to Disneyland.) You could have just one as a low-carb snack, but these dreamy tuna melts are so good, we eat both in one sitting for a protein-loaded meal.

Hungry Girl's Healthy Portabella Tuna Melts Recipe

Print Portabella Tuna Melts Print

Entire recipe: 317 calories, 11g total fat (3g sat. fat), 662mg sodium, 19.5g carbs, 4.5g fiber, 7g sugars, 38g protein

Click for WW Points® value*

Prep: 5 minutes
Cook: 20 minutes


1 tbsp. light mayonnaise

1 tsp. Dijon mustard

1/4 tsp. garlic powder

1/4 tsp. onion powder

One 5 oz. can albacore tuna packed in water, drained and flaked

1/4 cup finely chopped onion

2 large portabella mushroom caps (stems removed)

1 slice reduced-fat cheddar cheese, halved

Optional seasonings: salt, black pepper


Preheat oven to 400ºF. Lay a large piece of heavy-duty foil on a baking sheet, and spray with nonstick spray.

In a medium bowl, combine mayo, mustard, garlic powder, and onion powder. Mix until uniform. Add tuna and onion, and stir to coat.

Place mushroom caps on the center of the foil, rounded sides down. Place another large piece of foil over the mushroom caps. Fold together and seal all four edges of the two foil pieces, forming a well-sealed packet. Bake until slightly tender, about 14 minutes.

Cut packet to release steam before opening entirely. Remove foil, and carefully drain excess liquid from the baking sheet. Thoroughly blot away excess moisture from mushroom caps.

Fill mushrooms with tuna salad, and top each with half a slice of cheese. Bake until tuna is hot and cheese has melted, about 5 minutes.


HG Tip: Use a mushroom cleaning brush like this Amazon find to get your portabellas in recipe-ready shape!

High decadence with low effort… Watch how to make it here!

Hungry for More Stuffed Portabella Mushrooms?

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