Wash the fillets. Place them on a plate and salt and pepper them.
Combine mustard with cream and beat to mix well.
Soak herring in the mixture for 10 minutes.
Put the oats in the blender or food processor, slightly broken up.
Dip the herring in the broken oats and coat evenly.
Add oil to a large, heavy skillet; heat to medium-high. Turning once to insure crispness on each side. It will take about 3 minutes for the fillets to get brown.
Remove the herring fillets from the pan and allow them to cool down.
Serving Suggestions: Serve them in a bowl and garnish with a bit of mayonnaise. Serve with boiled potatoes or rice.