Preheat the oven to 400 degrees F. Season the cod fillets on both sides with the old bay seasoning, salt and pepper.

Remove the potatoes from the water and pat dry with towels. Cover with a damp cloth until dry. In a bowl add mustard, mayonnaise, feta cheese, cayenne pepper and tomato sauce. Mix well.

In a bowl add sour cream, mayonnaise and cream cheese. Fold together mixture, then add chives and fold. Set aside.

One at a time, coat the fillets in mixture and then place shredded potato mixture on top of each cod piece. Carefully lay the fish in a cookie sheet lined with foil. Place the cookie sheet in the oven and cook until the fish is cooked through and is golden brown. Plate and top with sour cream mixture.