Prep Glass: Fill a Collins glass with ice cubes. Give it a stir to chill it and set it aside.
Muddle Raspberries: In your shaker, add 5 fresh raspberries and 1 oz fresh lemon juice. Muddle to extract the flavor from the raspberries.
Add Simple Syrup: Add ⅔ oz simple syrup.
Add Gin: Measure and pour 2 oz Gin into the shaker as well.
Shake: Fill the shaker with ice, close it, and give it a good shake (10-15 seconds).
Strain: Take the Collins glass and use the cocktail strainer to remove any excess water inside. Then, using both the cocktail strainer and the fine strainer, strain the shaken drink into the ice-filled glass.
Top with Soda: Top off with approx. 3-4 oz soda water, adjusting to taste and to the size of the glass.
Stir: Using a bar spoon or long stirrer, stir gently to combine.
Garnish: Put a few raspberries on a cocktail skewer. Gently place it on top of the glass, sprinkle it with icing sugar, and serve immediately.