|dark chocolate, 60% to 62% cacao, chopped||.|
|condensed tomato soup, preferably Campbell’s|
|red-tinted buttercream and red or clear piping gel (it’s fine to use the Wilton tubed variety; see Note)|
In a food processor, process the chocolate until very fine.
In a 4-cup or larger microwavable cup with a spout (or in a medium saucepan, stirring often), whisk together the cream and tomato soup and scald it (heat it to the boiling point; small bubbles will form around the periphery).
With the motor of the food processor running, pour the cream mixture through the feed tube in a steady stream. Process for a few seconds until smooth. Scrape the ganache into a glass bowl and allow it to sit for 1 hour. Cover it with plastic wrap and allow it to cool at room temperature for several hours, or until the mixture reaches frosting consistency. The ganache keeps for 3 days at room temperature, for 3 weeks refrigerated, and for 6 months frozen.