This cocktail is a throwback to the classic era of cocktails, with a touch of modern flair. It is a sweet and sour drink that is sure to satisfy any sweet tooth. The base of this cocktail is made with a mixture of blackberry liqueur, fresh lime juice, and vodka. To give it a unique twist, I add a splash of triple sec and top it off with a splash of soda water. 

Ingredients:
- 1 1/2 oz blackberry liqueur
- 1 oz vodka
- 1/2 oz fresh lime juice
- 1/2 oz triple sec
- Splash of soda water

Instructions:
1. Fill a cocktail shaker with ice.
2. Add the blackberry liqueur, vodka, fresh lime juice, and triple sec to the shaker.
3. Shake vigorously for 15-20 seconds.
4. Fill a glass with ice.
5. Strain the cocktail into the glass.
6. Top it off with a splash of soda water.
7. Garnish with a lime wedge or fresh blackberries. Enjoy your Retro Panda Cocktail!