Place 1 tablespoon dried butterfly pea flowers in a heatproof container and pour 4 oz hot water over them. Steep for 5–10 minutes until deep indigo color develops.

Strain out the flowers through a fine mesh strainer. If you prefer a sweetened syrup, stir in 0.5 oz simple syrup while still warm. Cool to room temperature and chill until ready to use. Reserve 0.5 oz per cocktail.

Assembly — Colour Changing One

Prepare glass

Chill a highball or Collins glass by filling with ice and setting aside, or place in the freezer for a few minutes.

Mix base

In a cocktail shaker filled halfway with ice, add 2 oz Ketel One vodka, 0.75 oz Briottet Green Apple liqueur, 0.5 oz fresh lemon juice, and 0.5 oz simple syrup. Shake vigorously for 10–12 seconds until well chilled.

Add butterfly pea

Strain the shaken mixture into the chilled highball glass filled with fresh ice. Pour 0.5 oz chilled butterfly pea concentrate gently over the back of a spoon so it floats and gives an initial deep blue/purple layer.

Top with soda & watch the magic

Slowly top with 3 oz soda water. As the soda mixes and the citrus interacts with the butterfly pea, the drink will shift from blue/purple to a pinker/copper hue. If you want a more dramatic change, squeeze the reserved lemon wheel over the top to add a final burst of acid.

Garnish & serve

Garnish with a thin apple slice slid onto the rim and a lemon wheel. Serve with a long spoon or straw so the guest can swirl to further mix colors.