Step 1: To make the pistachio paste, add shelled pistachios to a food processor. Process on high speed for 3-5 minutes, scraping down the sides occasionally. The pistachios will go from coarse crumbs to a finer meal, then eventually release their oils and form a thick paste. Be patient; this takes a few minutes.
Step 2: Once a thick paste forms, add 1-2 tablespoons of hot water, 1-2 teaspoons of maple syrup (or honey), and the optional vanilla extract. Process again until smooth and well combined. The hot water helps create a smoother, more emulsified paste. Adjust sweetness to your preference.
Step 3: Brew 1-2 shots of espresso or prepare 1-2 ounces of strong coffee. Set aside.
Step 4: In a small saucepan or microwave-safe mug, gently heat your milk of choice until hot but not boiling. If using a steam wand or frother, heat and froth the milk until it's steamy and has a good layer of foam.
Step 5: In your serving mug, add 1-2 tablespoons of the homemade pistachio paste (adjust to desired strength). Pour the hot frothed milk over the pistachio paste and stir well until the paste is fully dissolved and incorporated into the milk.
Step 6: Gently pour the brewed espresso or strong coffee into the pistachio milk mixture. Stir lightly to combine. Garnish with a sprinkle of crushed pistachios, if desired. Serve immediately and enjoy your homemade Pistachio Latte Recipe!