This traditional Welsh dish consists of hard-boiled eggs baked in a bed of soft mashed potatoes, all smothered in a thick, creamy sauce made with leeks, butter, and cheese. The dish is then additionally topped with some more grated cheese. Anglesey eggs, called wyau ynys mon in Welsh, are best made with local ingredients: while the hardy leeks - once amongst the only vegetables grown in Wales - impart a subtle, sweet flavor to this simple seasonal supper dish, Welsh salted butter and Aberwen cheese turn it into something utterly sublime.