In a large bowl, add the fish, mashed potatoes, scallions, parsley, dill, time, cayenne pepper, salt, and pepper. Mash everything together, tasting the mixture and adjusting the seasonings as needed. Form the mixture into patties.

Pour the breadcrumbs onto a plate. Then dip each patty into the breadcrumbs.

Heat oil in the skillet over medium–high heat. Fry the patty on each side until golden and crispy. Drain on paper towels or paper bags. Squeeze lemon juice over each fish burger and serve.