2 oz of Pimm's No. 1 Cup
1/2 oz of Creme de banane (or banana liqueur)
3/4 oz of Pineapple Syrup
2 oz of Grapefruit Soda
3/4 oz of Lime Juice
Combine, add ice, shake and strain into a an ice filled large Old Fashioned glass. Garnish with a banana chip.