Add the shrimp, egg white, cilantro, scallions, coconut aminos, arrowroot starch, Umami Stir-Fry Powder or Diamond Crystal kosher salt, toasted sesame oil, minced garlic, and ground ginger in the bowl of a food processor. Pulse the shrimp and seasoning until everything is finely minced and a thick paste is formed.
Lay the tortillas on a clean surface and spoon one-fourth of the shrimp mousse on each tortilla.
Use an offset spatula or butter knife to spread the shrimp paste in a thin even layer on each tortilla. If desired, sprinkle the sesame seeds in a single layer on top of the shrimp paste.
Cut each tortillas into 4 wedges.
Heat a large cast iron skillet or non-stick skillet over medium heat. Pour in enough avocado oil to reach ¼-inch and wait for it to be shimmering.
Carefully add the gluten free shrimp toasts, shrimp-side down, in the oil and fry until golden brown, about 2-3 minutes.
Use a pair of tongs to carefully flip them over, and fry on the tortilla side for about 1 minute, or until golden brown.
Transfer the shrimp toasts to a cooling rack to drain. You can also drain them on a paper towel-lined plate or blot them with paper towels. Serve immediately.
Cooking in an air fryer? Spray the tops of the shrimp toast with avocado oil spray and place as many of them that fit in a single layer, shrimp-side-up, in the air fryer basket. Air fry the shrimp toast at 400°F for 4 to 5 minutes or until golden brown. Repeat until all of them are cooked.