Tom Collins

The spec

Two ounces of gin, an ounce of lemon, half an ounce of simple syrup, shaken and poured over fresh ice, then topped with about two ounces of soda. The soda is a listed ingredient here rather than “to taste” because it’s roughly a third of the drink and the difference between two ounces and four is the difference between a cocktail and a spritz.

Shake the sour part, then top. Shaking the soda kills the bubbles. Shake the gin, lemon, and syrup, strain over ice, then add the soda and stir once to combine.

Less sugar than a coupe sour. The soda adds dilution and length, so the Collins runs drier than a Whiskey Sour or Gimlet. Half an ounce is right; ¾ oz makes it taste like lemonade.

Where people disagree

• Old Tom gin. The drink is named for Old Tom, a slightly sweeter gin style. With Old Tom, drop the syrup to a barspoon. With London dry, keep the ½ oz. Two cards, or one card with two lines.
• Build vs shake. Building it in the glass is faster and fine for a crowd. It’s not as cold and not as integrated. For one drink, shake.
• Garnish. Lemon wheel and cherry is the classic. A lot of bars now do lemon only. Nobody has ever complained.

Make it yours

Swap the gin and you have the whole Collins family: whiskey (John Collins), vodka, rum. Swap the lemon for grapefruit and add a pinch of salt and it’s a summer drink that people will ask you about. Top with a dry sparkling wine instead of soda and it’s very nearly a French 75.

For a party, this is the card to batch: shake nothing, mix the gin, lemon, and syrup in a bottle (lemon squeezed that day), keep it cold, and pour 3½ oz over ice and top with soda per glass. The batching guide has the maths.