Is there a way to prep mutton in order to ease its strong flavor?
The flavor will vary greatly depending on the cut of meat and the preparation.


Different cuts (eg: chops and legs) taste very differently from one another (legs and tougher meat taste more gamey)
Ground lamb has almost no gamey flavor
Well done meat will taste less gamey than medium (Edit: regarding "done-ness" this how it tastes to me. Since answering, I've discussed this with someone else who says the opposite is their experience)
Cooking with a lot of vegetables or a flavorful starch will by contrast cut down on the strong flavor more than a bland starch. A bland starch will result in highlighting the strong gamey taste