Peel shallots, set flat-side down, slice. Chop to make fine dice. Finely chop skinned garlic. Trim membrane from chicken livers, core, peel, dice 2 apples. Melt 2 tbs of the butter in frying pan, add diced apples with salt and pepper to taste. Saute, stirring frequently, until tender, 5-7 minutes. Transfer to bowl with slotted spoon. Melt 2 tbs more butter in the pan, add livers, salt and pepper, fry, stirring, until brown on outside, 2-3 minutes. Scrape chopped garlic and shallots into pan, continue cooking, stirring, until shallots slightly softened, 1-2 minutes. Remove a liver, slice into it - should be very brown but still pink in centre. Increase heat to medium high. Pour Calvados into pan, bring to boil. Hold lighted match to pan's side, set Calvados alight. Baste chicken livers until flames subside, about 20-30 seconds. Let livers cool. Puree mixture in food processor until almost smooth. With wooden spoon or electric mixer, cream 150 grams butter until very soft. Add chicken liver puree with apples to this. Mix well with wooden spoon, season to taste. Spoon into 6 ramekins, smoothing tops with back of a spoon dipped in hot water. Cover, chill until firm, 2-3 hours. Garnish: Core remaining apple with skin on, cut into 6 slices/rings. Melt remaining butter, fry slices, sprinkling with half the sugar. Turn slices over, sprinkle with rest of sugar, fry over medium heat until caramelized and brown, about 2-3 minutes on each side. Transfer to a plate. Make some toast, serve with an apple slice and mint spring on each pate and with the toast.