Sprinkle sesame seeds and a little salt over a sheet of gim. Quickly dip a square rice paper sheet in water and place it over the gim. Fold any excess rice paper onto the back. If using round rice paper, trim any excess and patch uncovered corners so the surface is mostly covered.
Cut into 4 squares and place into small microwave-safe sauce bowls. Microwave for 2 min.
Toss the avocado with lime juice and a pinch of salt. Mix the tuna, soy sauce, sesame oil, rice vinegar, sriracha, green onion, and sesame seeds.
Using a ring mold, layer yuzu ponzu, avocado, and tuna tartare. Top with jalapeño, microgreens and spicy mayo
