Tuna Stuffed Cherry Tomatoes

⏲ ~47 min total · prep 17 · cook 30 · 4 servings

By the KFI Test Kitchen · Tested & approved by Jason Lieu, KFI recipe editor

Published Sep 15, 2026 · Updated Sep 15, 2026

Ingredients

• 24 firm cherry tomatoes (about 1 pint)
• Two 5-oz cans tuna, drained well
• 1/3 cup mayonnaise
• 1 celery rib, minced
• 1 tbsp fresh dill, minced, plus small sprigs for garnish
• 2 tsp fresh lemon juice
• 1 tsp Dijon mustard
• 1/4 tsp salt
• 1/8 tsp black pepper

Instructions

1. Slice a thin cap off the top of each tomato and scoop out the seeds and pulp with a 1/4-teaspoon measuring spoon, leaving 1/4-inch walls so they hold their shape.
2. Turn the tomatoes upside down on paper towels and let them drain for 10 minutes while you make the filling.
3. Mash the tuna with the mayonnaise, celery, minced dill, lemon juice, Dijon, salt, and pepper until it holds together when pressed against the bowl.
4. Spoon the filling into a zip-top bag, snip 1/2 inch off one corner, and pipe it into each tomato, mounding it just above the rim.
5. Chill the filled tomatoes for 20 minutes so the filling firms up and the tomato flavor concentrates.
6. Cap each one with a tiny dill sprig and serve cold.

Why this recipe works

• A 1/4-teaspoon spoon as a corer Scraping with the small measuring spoon leaves 1/4-inch walls, and those walls are what keep 24 tomatoes standing upright on a platter. A bigger spoon punctures, and a smaller one takes forever.
• Ten minutes upside down Draining the hollowed tomatoes on paper towels pulls the pooled juice out of the cavities. Dry walls hold the filling; wet walls weep it back out within the hour.
• Piped from a zip-top bag A 1/2-inch snip turns the bag into a piping bag and fills each tomato with an even mound above the rim. Spoons smear the rims and leave fingerprints all over the platter.

Tips for making this recipe well

Buy firm, then pick firmer

The ingredient line asks for firm cherry tomatoes, and that word matters at the hollowing stage. Any tomato that dents under a thumb will collapse once its seeds are out.

Do not chase the seeds too deep

Stop scraping when the cavity is clean and the walls are still 1/4 inch. Thin walls split under the pressure of the filling.

Mash until it holds

The filling is ready when it holds together pressed against the bowl. Loose filling sags after the chill instead of mounding.

Respect the 20-minute chill

Cold firms the mayonnaise filling and concentrates the tomato flavor at the same time. Serve straight from the fridge, capped with the dill sprigs.

Salt was measured for the filling

The 1/4 teaspoon seasons the tuna mixture, and the tomatoes bring their own juice to each mouthful. Resist re-salting the tomatoes themselves.

Serving suggestions

This is the cold platter that empties first at any table it lands on. Twenty-four tomatoes, 1.3 net carbs a serving, and 40 minutes that are mostly hollowing and waiting. Line them up in tight rows on a flat platter, cap each with a tiny dill sprig, and serve them cold from the fridge. They read as party food, but with a green salad they carry a light lunch without apology.

Storage and meal prep

The filling keeps 3 to 4 days in a covered container, and hollowed tomatoes hold a day ahead in the fridge if you leave them upside down on towels. Once filled, the tomatoes are at their best within 24 hours; the walls soften slowly as the salt pulls juice. Skip the freezer entirely, since raw tomatoes turn mealy and watery when thawed and the platter goes with them.

Variations worth trying

• Shrimp filling Swap the tuna for 10 oz of finely chopped cooked shrimp and add an extra pinch of dill.
• Basil for dill Minced basil in the filling and small basil leaves as caps leans the flavor Italian.
• Mini pepper boats Halve small sweet peppers lengthwise and fill the same way; no coring, and they hold their shape for days.
• Smoked paprika in the mix A 1/4 teaspoon of smoked paprika in the filling echoes the color of the tomatoes and adds quiet depth.

Frequently asked questions

Can I fill them the night before?

You can, and the platter holds a day covered in the fridge. Expect the walls to soften slightly; add the dill caps right before serving so they stay bright.

What kind of tuna works best?

Any drained canned tuna works, with well drained being the operative part. Oil-canned tuna brings more flavor; tuna canned in water needs a teaspoon more mayonnaise.

Why did my tomatoes turn soggy?

Usually the draining step was skipped or shortened. The 10 minutes upside down on paper towels matters as much as the hollowing.

Can I skip the piping bag?

A small spoon fills them fine, and it is slower and messier. The bag with a 1/2-inch snip gives the clean, even mounds that make the platter look professional.

How many should I plan per person?

They are two mouthfuls each, so figure four to six per guest alongside other food. A pint makes a full platter for a small gathering.

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