Warm the butter to room temperature, it should be easy to spread. Remove the oil from the glass with salmon substitute, add salmon substitute to the butter. Cut the onion into fine pieces (you should still feel the pieces while eating, but they shouldn`t be too obstructive when spreading the mixture), add to the butter.
Now mix the mass well.
The salmon butter is ideal for a delicious spread, preferably on light bread. But I also like them with jacket potatoes.