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put the jalapeños in a full bottle of mezcal and let sit ⏲️ overnight.
combine 1 oz each of jalapeño-infused mezcal, campari, and sweet vermouth.
add ice and stir.
add one big ice cube to a rocks glass. strain stirred ingredients into glass.
cut a slice of grapefruit peel. express the oils over the drink, rim the glass with it, then add as garnish.