Chop the chocolate – Finely chop the dark chocolate and place it in a heatproof bowl.

Heat the cream – Warm the cream in a saucepan until just below boiling.

Combine chocolate and cream – Pour the hot cream over the chopped chocolate and let it sit for a minute.

Stir until smooth – Stir the mixture until the chocolate melts completely and forms a smooth ganache.

Add butter – Mix in the butter until fully melted and combined.

Chill the mixture – Place the ganache in the refrigerator for 1–2 hours until firm enough to handle.

Shape the truffles – Scoop small portions and roll into balls using your hands.

Coat the truffles – Roll each truffle in cocoa powder, chopped nuts, or sprinkles.

Set and store – Place the truffles on a tray and refrigerate until ready to serve.