Line a baking sheet with waxed paper.Place chocolate in a bowl set over a saucepan of simmering water. Stir occasionally, until melted, 3 to 5 minutes. Remove from heat.
Holding a strawberry by the stem end, dip it in the melted chocolate, letting the excess drip off, then sprinkle chocolate-covered portion with pistachios.then transfer to the prepared baking sheet. As you set the strawberry down, slide it ½ inch to the side to prevent the formation of a chocolate “foot.”
Chill chocolate-dipped strawberries at least 15 minutes to set chocolate. (Strawberries should not be stored in refrigerator longer than 1 hour as condensation drops may collect on the chocolate.)