Pour the heavy cream into a small saucepan and warm over low heat until just steaming, about 3-4 minutes. You should see gentle steam without vigorous bubbling.
Place the cocoa powder and butter in a heatproof mixing bowl. Pour the hot cream over and let sit for 1 minute.
Stir the mixture with a spatula until smooth, glossy, and well combined, creating a thick chocolate paste.
Add the powdered sugar, vanilla extract, and a pinch of salt. Mix thoroughly until the mixture is thick, shiny, and cohesive.
Cover the bowl with plastic wrap and refrigerate for 1-2 hours until the mixture firms up to a fudge-like consistency.
Once chilled and firm, use a teaspoon or small cookie scoop to portion out the mixture.
Roll each portion quickly between your palms to form small, smooth balls about 2 cm in diameter.
Optional: Roll the truffles in cocoa powder, chopped nuts, or shredded coconut for a decorative and flavorful coating.
Place the finished truffles on a parchment-lined baking sheet and refrigerate for at least 30 minutes to set.
Serve the truffles at room temperature or chilled, enjoying their rich, fudgy interior and smooth exterior.
