Inspired by Proof & Provision's Retox cocktail (which I've never tried). I wrote down the ingredients and gave it a shot. Full story here http://www.backdownsouth.com/2013/05/drink-this-takeover-hey-hermano/
2 oz 100% agave tequila
3/4 oz maple chili syrup
3/4 oz fresh lime juice
2 dash orange bitters
Syrup --> 1:1 maple syrup to water. Add sliced Serrano peppers a few at a time and seep, tasting every few minutes until desired spiciness. Make sure it has a kick.
Shake all ingredients and strain into a glass with some large ice cubes. Garnish with a lime slice.