Recipe by Barlow Gilmore, The Weekend Mixologist
Add all ingredients except soda to a shaking tin and then add ice. Shake very well and strain into an 8oz fizz glass. Beat with a barspoon while adding soda to the rim of the glass. Slowly add more soda to "lift" the head above the rim of the glass. Garnish with a peanut.
Peanut Butter Syrup:
Heat 1 cup water in a pot until simmering, add 1 cup sugar and 2 tablespoons peanut butter and stir until incorporated. Remove from heat and reserve.