The two Davids’ combined work was impossible to sum up in a single cocktail, so they asked that we conjure one cocktail that could function equally well with two different base spirits, Old Tom gin for David Hollenberg and tequila for David Piscuskas. Both were gratified with their respective cups.
Combine all ingredients in a mixing glass over ice and stir until well chilled, up to 45 seconds. Strain into a double rocks glass with one large cube. Twist a peel of orange, skin side down, over it, and discard the peel.
Cinnamon tincture:
In a Mason jar or other sealable container, combine roughly 500 grams of cinnamon stick with one liter of a very strong neutral spirit, such as Everclear or 100-proof vodka. Leave for at least a week, shaking jar once a day or so. You can extract small amounts of the tincture, which will get stronger the longer you leave it on the cinnamon, and replace what you take with fresh spirit. Keeps indefinitely.