Where Drinks Experts Go in London for the Perfect Paloma

May is, apparently, London’s Paloma Month, culminating in World Paloma Day on 22 May. A quick look behind the curtain, however, suggests no real historical or cultural link between the pink tequila-and-grapefruit cocktail and the month itself—making the ‘celebration’ feel more like a well-timed marketing invention than an established tradition.

Which is curious, given that teq...