Zucchini Tuna Melts
Yield: 2 servings (recipe easy to scale up)
Naturally gluten-free, low in carbs, and high in flavor, Zucchini Tuna Melts are a deliciously fun way to enjoy a seasonal abundance of zucchini and summer squash.


  • 1 large (12–16-oz) or 2 small (6–8-oz) zucchini or summer squash
  • 1 (5-ounce) can tuna, well drained and flaked (I use water-packed; oiled-packed is fine too)
  • 2 tablespoons finely diced celery
  • 1 tablespoon minced green onion (could substitute sweet onion, shallot, or chives)
  • 1 scant tablespoon capers, rinsed and drained (optional)
  • 1 teaspoon (5g) Dijon mustard (may use an equal amount of sriracha instead)
  • 2 tablespoons (26g) mayonnaise
  • ¼ cup (1oz) shredded mozzarella cheese
  • Kosher salt and ground black pepper to taste (I use ⅛ teaspoon each for the tuna mixture plus a pinch for the unstuffed zucchini)
  • ¼ to ⅓ cup (1- 1⅓oz) shredded sharp cheddar cheese


  1. For the tuna mixture: In a mixing bowl, combine the tuna, celery, green onion, optional capers, Dijon, mayo, shredded mozzarella, and ⅛ teaspoon each kosher salt and pepper. Mix until combined. Advance prep tip: the tuna mixture may be prepared up to one day in advance. Cover and refrigerate until needed.

    Preheat the oven to 375℉ and line a baking sheet with parchment paper or foil.

    Slice the zucchini lengthwise into even halves. Using a small spoon or melon baller, scrape out the seedy center and a little bit of the flesh, leaving a border of about ⅓ to ½ inch on all sides. (Discard this or save for another use.)

    Arrange the zucchini shells on the baking sheet. Sprinkle the insides of the zucchini with a pinch of salt and pepper. Bake for 12-15 minutes, or until just short of tender. Remove the zucchini from the oven.

    Evenly fill the halves with the tuna mixture, and then sprinkle with the shredded cheddar. Return to the oven for about 10 minutes, or until the tuna is hot throughout and the cheese is melted. If desired, you may place on the top rack of the oven for the last few minutes to lightly brown the cheese. Or broil for a minute or so, watching very closely so as not to burn. Enjoy!

    Leftovers may be refrigerated for 3 to 4 days and gently warmed in the oven or microwave.


For those who use a kitchen scale, the weight of the tuna mix is ~195g so plan on adding 96g per large zucchini half (or 48g per English muffin half if you’d like to make a traditional melt on toasted bread).

More recipes at FountainAvenueKitchen.com