Fold a nori sheet and cut in half. Set the half aside for now.
Using a full nori sheet, place the rice onto the nori and spread it evenly, creating a rectangle that covers ⅔ of the nori.
Sprinkle furikake all over the rice.
Place salad greens on top of the rice, followed by the cucumber on top of the greens. Next, place the imitation crab meat in front of the cucumber.
Spread the tuna mayo on the remaining visible parts of the rice, but leave ½ inch of rice space uncovered.
Place the crispy spam pieces on top of everything.
Drizzle unagi sauce on top.
Wet the end of this nori sheet with water and attach that ½ you cut earlier onto it by pressing the seams together. Then add a little rice on the ends of that ½ nori sheet. This helps the ends of the burrito to stick better.
Roll the nori using a bamboo mat, like a burrito.
Wrap the burrito with parchment paper tightly, using the burrito wrap method.
Slice gently in half, and enjoy!