In a mixing glass, combine all ingredients (except Lemon-Ginger Foam) with ice and shake well. Strain over fresh ice. Top with Lemon-Ginger Foam and garnish.
For the Lemongrass Infused Gin:
Combine lemongrass and gin. Leave in room temperature for about 24 hours. Or sous vide for 1.5 hours and let cool.
For the Mango Seed Dill Shrub:
Combine mango seeds, chopped dill and sugar and let sit at room temperature until sugar dissolves and sugar turns into liquid, 24 to 48 hours. Add vinegar and let sit for additional 12 to 24 hours, depending on desired flavor. Taste and strain out all solids.
For the Lemon-Ginger Foam:
Combine all ingredients into an ISI Soda/Cream Siphon, and close tight. Charge with ISI n2o Cream Charger and let cool. For a thicker consistency double charge with a second n2o charger. Refrigerate when not in use.
Recipe by Tony Pereyra, Bar & Beverage Solutions, The Spirits in Motion