01 - Immerse pistachios in filtered water and allow to soak overnight or for at least 6 hours. Drain and rinse thoroughly.
02 - Combine soaked pistachios with 3 cups filtered water, vanilla extract, maple syrup or honey, and a pinch of sea salt. Blend until thoroughly smooth.
03 - Pour blended mixture through a nut milk bag or fine mesh sieve into a pitcher. Discard the solids or reserve for baking applications.
04 - Transfer pistachio milk to a saucepan and warm gently over medium heat, whisking until steaming but not boiling. Sweeten to taste if desired.
05 - Brew two shots of espresso or strong coffee using an espresso machine or coffee maker.
06 - Pour hot pistachio milk into cups, reserving some froth. Add espresso to each and stir gently to combine.
07 - Top with reserved milk froth and garnish with crushed pistachios if desired. Serve immediately.