Chop the carrot into thin strips.
Chop the cucumber into thin strips, removing the seeds.
Cover your bamboo sushi mat with plastic wrap and place it on a cutting board.
Cut each sheet of seaweed in half with a pair of scissors.
Place half a seaweed sheet on the bamboo mat, shiny side down. If you’re a first-time sushi-maker, lay the seaweed vertically.
Using your hands, spread ¾ cup of sushi rice over the seaweed, patting it to smooth but not squashing it.
Flip over the seaweed strip so that the rice is now facing downwards.
Place the filling of the roll (sliced carrots, cucumber, and one soft shell crab tempura) along the center of the nori. Leave the crab’s legs extending beyond the nori to form the “spider’s legs.”
Drizzle with unagi sauce.
Place your thumbs underneath the edge of the bamboo mat, lifting it up and over the filling.
Use your fingers to keep the filling from spilling out.
Applying firm pressure, roll the mat away from you until the ends of the mat meet.
Gently squeeze the sushi roll.
Remove the mat and plastic wrap.
Slice the sushi roll into eight bite-sized pieces.
Serve with a drizzle of unagi sauce.