Hot fudge has to be one of my favorite things on this planet. On ice cream, drizzled over cake or brownies, mixed into milk – you name it, I love it. Sadly, I’d always relied on the kind from the jar to get my fix. But, as with some of my other favorite store-bought items, I wanted to learn to make it at home.
8 ounces semisweet or bittersweet chocolate (60%–72% cacao), chopped
Bring sugar, agave syrup, and 2 Tbsp. water to a boil in a small deep heavy saucepan, stirring to dissolve sugar. Prop a candy thermometer in pan with bulb submerged in syrup. Boil without stirring until thermometer registers 265°, 8–10 minutes. Add cream, milk, and butter. Whisk until butter is melted and mixture is smooth.
Remove from heat; add chocolate and whisk until melted and mixture is smooth.
DO AHEAD: Can be made 2 weeks ahead. Transfer to a microwave-safe bowl. Let cool completely; cover and chill. Reheat in microwave in 10-second intervals, stirring occasionally, until heated through.