Aperol Spritz

Three parts prosecco, two parts Aperol, one part soda. Low in alcohol, impossible to get wrong, built for the afternoon.
Negroni

Equal parts gin, Campari and sweet vermouth. Three ingredients, no measuring gymnastics, and nowhere to hide.
Manhattan

Rye, sweet vermouth and bitters. Two ingredients and a dash, and the vermouth is the one that decides whether it works.
Old Fashioned

Whiskey, sugar and bitters — the drink that defined the word cocktail, and still the best argument for it.