1 In a bowl, put the butter and beat until smooth.
2 Gradually, beat in the mustard, add salt and pepper to taste.
3 Shape into a long roll.
4 Wrap the roll in the foil and pack in a freezer bag.
5 Seal the bag, label and freeze.
6 Carefully remove the wrappings and using a knife dipped in hot water, cut the frozen butter into slices .
7 Tastes great with grilled (broiled) gammon and baked fish.