The Tonica Recipe

Steep butterfly pea

Place 1 tsp dried butterfly pea flowers into a small heatproof container and pour 2 oz hot water (just off boil). Steep 4–6 minutes until deep blue, then strain to remove flowers. Let the tea cool to room temperature (5–10 minutes).

Color and blend with gin

Combine 2 oz Western Son Gin with 0.5–1 oz of the cooled butterfly pea tea (adjust for color intensity) in a small bottle or jar. Stir gently and let sit 5 minutes for color to marry. This yields butterfly pea–infused gin with a vivid blue hue that will change with citrus.

Fill a highball or Collins glass with ice to chill.

Into a mixing glass (or shaker without shaking), add 2 oz of the butterfly pea–infused Western Son Gin and 0.75 oz fresh lemon juice. If you prefer a touch of sweetness to balance acidity, add 0.25 oz simple syrup; otherwise omit.

Stir the gin and lemon (and simple syrup if used) with ice for about 10–15 seconds to chill and slightly dilute.

Strain the mixture into the prepared ice-filled glass.

Top gently with 4 oz Fever-Tree Indian Tonic Water poured over the back of a spoon or down the side of the glass to preserve the fizz and create a clean layer. The acidic lemon will shift the butterfly pea color from blue toward purple/pink—allow the color to settle for a moment.

Garnish with a lemon wheel on the rim and/or a fresh lemon twist. Serve with a stirrer or straw.

Serves 1. Estimated total time includes infusion preparation; if you pre-infuse gin in advance (refrigerate up to 24 hours), the cocktail assembly time is ~3 minutes.

Adjust tonic quantity to taste for more or less bitterness. For a more dramatic color change, pour the lemon juice in last or float a thin lemon wheel on top.