Slice the cucumbers right down the middle length wise.
Then, using a spoon, gently scrape out the insides.
Cut the halves in 4-5 equal pieces depending on the length of your cucumber.
Discard the scooped seeds and set the cucumber "boats" aside on a large platter.
In a small bowl add the drained tuna and gently mash with a fork until it's all flaked. Add in the celery, green onion, yogurt, dill, lemon, smoked paprika, sea salt and pepper.
Mix all of the ingredients together with a fork until everything is nicely combined.
Place the fresh tuna salad mixture into each cucumber half.
Top with green onion slices, and sprinkle with a pinch of chili flakes.