How to Make It
Place 1 1⁄2 pounds of the shrimp into a food processor. Add celery, eggs, chili pepper and soy sauce and pulse until there is a mix of finely minced and coarsely chopped pieces of shrimp, about 5 (5-second) pulses.
Gently fold the panko crumbs, lemon zest, parsley and scallions into the shrimp mixture to combine. Chop remaining 1/2 pound shrimp into 1/2-inch pieces and fold into the mixture. Season with 1⁄2 teaspoon of salt and 1⁄2 teaspoon of pepper.
Shape mixture into 6 (five-ounce) balls. Heat 1 1⁄2 teaspoons oil in a medium nonstick skillet over medium-high heat until oil begins to shimmer. Place 3 shrimp balls in pan, flattening with a spatula to 1/2-inch thickness. Reduce heat to medium and cook until the edges turn pink, and the burger looks golden, about 3 to 4 minutes. Turn over and cook 3 minutes or until done. Repeat with remaining oil and shrimp balls.
Place the burgers on the potato buns and serve.