Salt and pepper the fish. Chop up your celery and green onions.

Place fish in a frying pan and cover with about 3/4 cups milk, or until mostly covered, but not all the way covered. The amount of milk you use will vary depending on the size of the filets. Bring to slightly under a boil and season with herbs, salt and pepper. Simmer for about 5 - 10 minutes or until cooked through and fish flakes apart.

Meanwhile, combine celery, green onions, 1 tablespoon mustard, 2 tablespoons of the mayo, 1/4 tablespoon of the horseradish, and dill into a bowl. Note: these measurements are a bit "give or take" depending on the size of your filets. Add more or less to your taste.

Take a good handful of the mixture and squeeze out any excess liquid. Form into patties. These should be sturdy enough to stay together.

Heat vegetable oil and add patties when hot. Cook about 2-3 minutes on each side or until nicely cooked through.

Mix the remaining mustard, mayo, and horseradish, with a splash of olive oil, and vinegar to make a sauce.