Last night made lots of these:
1 oz Olmeca Altos Reposado tequila
1 oz Del Maguey Vida mezcal
1.5 oz Pineapple juice
1 oz Lime juice
0.5 oz Agave nectar
In shaker muddle jalapeno slices with lime juice and agave nectar. Add rest of ingredients. Shake and strain into cocktail glass.
Original Picosito recipe has more pineapple juice and agave nectar (plus no jalapenos). However I feel it's way too cloying. Plus adding the jalapeno gives it a nice umami kick.