Muddle the cucumber slices in a mixing glass. Add spirits and ice, then stir and fine-strain into a chilled coupe. Top with 2 oz. Moët Imperial Champagne. Garnish with a lemon twist.
The cucumber reinforces the vegetal notes of the earthy tequila, which stands in for sweet vermouth in this regal Americano variation. —Jim Meehan, Summer 2010