1. Bring steak sauce and wine to a boil. Reduce heat to a simmer and add chocolate. Stir until chocolate is melted and blended; simmer for about 40 minutes. The reduction will measure between 1/3 to 1/2 cup.
2. Whip Plugrá Butter until smooth and light.
3. Add reduction to butter and mix until well combined. Store in an airtight container in the refrigerator until ready to use.