As noted in Food & Wine magazine, Queen Elizabeth II's preferred mixed drink was a gin & Dubonnet cocktail (it was the favorite of the Queen Mother's as well).
It's a simple recipe with three ingredients: Dubonnet (a French aperitif), gin (the Queen, rather patriotically, prefers Gordon's London dry gin), and a lemon slice.
1 ounce gin
2 ounces Dubonnet
Half lemon wheel
Pour one part gin and two parts Dubonnet into a small wine glass. Add the lemon, and top with two ice cubes, sinking the lemon.
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