Chop veggies. Chop the celery, red onion, green onion and cilantro to mix with the tuna. Thinly slice the cucumber, red bell pepper and carrots into matchsticks to add into the wraps.: Feel the crispness as you run your knife through the celery , red onion , green onion , and cilantro , the aromatic burst will become noticeable in the air, signalling freshness. Chopping fine ensures the flavors distribute evenly and each bite has a balance of texture, making the mixture cohesive when folded with the creamy elements. A common mistake is chopping inconsistently, which can create pockets of overpowering flavor; aim for uniform pieces. Keep your fingers curled under and use a sharp knife to avoid bruising the herbs or smashing the vegetables, which would release excess moisture and dilute the filling.
Make spicy tuna. In a small bowl, mash together the tuna and avocado, until combined. Stir in the sriracha, dijon mustard, celery, red onion, green onions, cilantro and salt and pepper, mixing well.: You will hear a satisfying crunch as you slice through the vegetables, the clean sound is one of the signs they are perfectly fresh. Thin matchsticks allow the veggies to layer neatly inside the tortillas and prevent large pieces from puncturing the wrap. This technique helps maintain a pleasant mouthfeel and keeps bites tidy. Avoid cutting thick strips, as they can overpower the tuna mixture and make the wrap harder to bite into evenly; if you have a mandoline, use it carefully to speed this step.
Assemble wraps. To assemble wraps, top each tortilla with leafy greens, sliced veggies and divide the spicy tuna mixture evenly among the wraps. Tightly roll up the tortillas. Slice and enjoy!: As you mash the tuna with the avocado , notice how the mixture turns silky, the aroma of tuna becomes creamier and more integrated, and the avocado softens any metallic edge. Stir in the sriracha , dijon mustard , chopped celery , red onion , green onions , cilantro , and season with salt and pepper , the heat should bloom and the mustard should add a bright lift that balances the fat. Mixing gently preserves some texture while producing a spreadable consistency, which helps when assembling the wraps. A frequent pitfall here is overmashing the avocado, which can make the filling too loose and watery; mash until creamy but still slightly chunky, and adjust seasoning after mixing, tasting as you go.
Assemble wraps: Lay a warmed tortilla flat and arrange a handful of leafy lettuce , followed by a portion of matchstick cucumber , red bell pepper , and carrots , then spread the spicy tuna mixture on top; you will see a pleasing contrast of colors and feel the cool crunch against the creamy filling. Rolling tightly helps the layers cling together and prevents the filling from shifting, and the slight resistance as you tuck the edge under tells you it is snug. If the tortilla cracks when rolling, warm it a little longer to make it pliable. A mistake to avoid is overfilling which makes the wrap difficult to close; keep the filling in a central strip to make rolling easy and neat.
Slice and enjoy: When you slice the wraps, you should see a neat cross section of vibrant vegetables and the creamy tuna core, the visual cue that the wrap is balanced. Serving immediately preserves the crispness of the vegetables and the fresh herb aroma. If you need to hold them for a short time, wrap them in parchment to retain structure, but avoid long storage as the avocado will darken and the tortilla may soften. A tip is to serve cut side up for best presentation, and if the filling seems loose, allow it to rest briefly in the refrigerator to firm up before slicing.