1Make Sour Cream Dill Sauce.
2Mix tuna, 1 cup of the cornflake crumbs, mayonnaise, onions, mustard and egg. Shape mixture into four 4-inch patties. Coat patties with remaining 1/2 cup cornflake crumbs, pressing lightly to coat both sides.
3Heat oil in 10-inch nonstick skillet over medium-high heat. Cook patties in oil 2 to 3 minutes, turning once, until light golden brown. Serve with sauce.