If you are unable to find peppered mackerel, use plain. Be sure to add lots of extra pepper in this case.
I had 300g of peppered mackerel so I used 70g crème fraiche in lieu of the recipe's yoghurt and cheese (as I had lots and it's ideal), 35g horseradish sauce., 20g lemon juice., and extra black pepper. We found these proportions worked very well. Delicious with sliced dill pickle and thin crispy buttered toast. - 11 Aug 2017
This is the most delicious mackerel pate I've ever made! - 14 Feb 2016