Place chicken in a large bowl and set aside. Place the water chestnuts, scallions and jalapeno pepper into the food processor and pulse until finely chopped. Toss the water chestnut mixture into the bowl with the chicken, add cilantro, salt and egg white and gently mix together with your hands until just combined.
Line a cookie sheet or other flat-bottomed dish that will fit in your freezer with parchment paper. Using a spoon and moistened hand, form the mixture into small, bite-sized patties, and lay them on the prepared sheet, adding more layers of parchment paper as necessary. Dipping the spoon in water and continuing to moisten your fingers will help prevent sticking.
Place the tray in the freezer until patties are frozen solid. Peel the chicken patties off the parchment and store them in plastic freezer bags or other airtight container until ready to cook.
Preheat barbecue and reduce temperature to MEDIUM/LOW. Brush or spray both the chicken patties and the grill liberally with vegetable oil to prevent sticking. Grill from frozen until cooked through, about 10 minutes, creating Perfect Grill Marks.
Spicy Dipping Sauce: Mix all ingredients in a small glass bowl.