Step 1

Make the ponzu sauce: In a small bowl, combine the soy sauce, mirin, lemon zest and juice, grapefruit juice, orange juice, bonito flakes, and kelp. Mix until well combined, then cover and let steep in the refrigerator overnight.

Step 2

Make the lime crema: In a small bowl, mix together the sour cream, lime zest and juice, garlic, and salt until smooth. Refrigerate until ready to use.

Step 3

Prep the roll: In a medium bowl, combine the imitation crab, mayo, Sriracha, sesame oil, and togarashi. Mix until well combined, then season with salt and pepper to taste. Refrigerate until ready to use.

Step 4

Melt the butter in a small pan over medium-low heat. Add the asparagus and garlic and sauté until the asparagus is tender, 2–3 minutes.

Step 5

In a separate small pan over medium heat, toast the cooked quinoa until darkened in color and crispy, 4–5 minutes.

Step 6

Assemble the roll: Slice the tuna about ⅛ inch thick.

Step 7

Lay a sheet of plastic wrap on top of the sushi mat. Carefully arrange the tuna slices, starting at the bottom of the mat, into a 9½ x 3½-inch rectangle. Spoon the crab mixture on top of the tuna toward the bottom of the mat in a thin line. Place the asparagus and avocado on top of the crab mixture, then spoon the tobiko next to the crab. Roll the sushi tightly away from you, leaving about ½ inch of tuna exposed, then roll again until closed tightly. Refrigerate the roll for 30 minutes.

Step 8

Trim the ends, then slice the roll crosswise into 8–10 ½-inch-thick pieces. Transfer the sushi to a plate. Spoon a small dollop of lime crema on top of each piece and sprinkle the toasted quinoa over the top and sides. Serve with the ponzu sauce alongside for dipping.

Step 9

Enjoy!