01 -
Grease an 8"-x-4" loaf pan with cooking spray. Line with parchment paper, folding sides to fit snugly, securing with clips, and grease parchment with cooking spray.
02 -
In a large bowl, whisk together milk, sugar, heavy cream, cocoa powder, cornstarch, and salt until smooth.
03 -
Strain milk mixture into a medium saucepan over medium heat. Stir constantly to prevent sticking. Bring to a simmer and cook for 2 minutes, stirring continuously.
04 -
Reduce heat to medium-low and add chocolate chips. Stir until melted and the mixture is smooth.
05 -
Remove pan from heat and pour the chocolate-milk mixture through a fine mesh sieve into the prepared pan. Refrigerate until set, at least 4 hours.
06 -
Carefully unmold chilled cake onto a plate, peel off parchment, and dust with additional cocoa powder.
07 -
Heat a knife blade in boiling water, wipe clean, and slice the cake. Repeat reheating as needed. Alternatively, use a kitchen torch to heat the blade. Serve chilled.