Equipment
Ingredients
Dairy Liquids
- 350 ml whole milk
- 50 ml heavy cream
Thickening Base
- 4 egg yolks, room temperature
- 60 g granulated sugar
- 25 g cornstarch
- 15 g dutch-processed cocoa powder
- 2 g kosher salt
Enrichment & Flavor
- 120 g semisweet chocolate chips
- 30 g unsalted butter, diced, room temperature
- 5 ml vanilla extract
Nutrition (per serving)
Method
Place the semisweet chocolate chips, diced butter, and vanilla extract into a large mixing bowl. Set a fine mesh sieve directly over the bowl and set aside.
In a medium mixing bowl, aggressively whisk the egg yolks, granulated sugar, sifted cornstarch, sifted cocoa powder, and kosher salt until the mixture becomes slightly pale and very smooth. The cocoa powder will make it thick and paste-like initially.
Combine the whole milk and heavy cream in a heavy-bottomed saucepan. Place over medium heat and warm until it reaches a gentle simmer at around 85 degrees Celsius / 185 degrees Fahrenheit, with small bubbles forming around the edges of the pan.
Slowly pour about one-third of the hot milk mixture into the egg yolk bowl in a thin, steady stream while whisking continuously. This tempers the eggs to prevent them from scrambling.
Pour the tempered egg mixture back into the saucepan with the remaining hot milk. Cook over medium heat, whisking constantly and vigorously, scraping the bottom and sides of the pan.
Once the mixture thickens significantly and begins to bubble, continue to boil while whisking for exactly 1 minute. This ensures the starch is fully activated and the raw cornstarch flavor is cooked out at 95 degrees Celsius / 203 degrees Fahrenheit.
Immediately remove the saucepan from the heat and pour the hot custard through the fine mesh sieve into the large bowl containing the chocolate chips, butter, and vanilla. Discard any cooked egg bits caught in the sieve.
Let the hot mixture sit undisturbed for 1 minute to melt the chocolate and butter. Then, using a rubber spatula or a clean whisk, gently stir in concentric circles from the center outwards until completely smooth and emulsified.
Press a sheet of plastic wrap directly onto the surface of the hot chocolate pastry cream to prevent a rubbery skin from forming. Transfer to the refrigerator and chill completely until firm.
Chef's Notes
- Vigorously whisking the egg yolk and sugar mixture immediately is critical; if sugar sits on undisturbed yolks, it will draw out their moisture and cause hard, un-dissolvable sugar-egg clumps.
- Dutch-processed cocoa is specified because its neutral pH prevents it from reacting with the dairy and producing an overly acidic, sharp flavor. It also provides a darker, richer color.
- For an incredibly light and airy variation, you can fold equal parts of whipped heavy cream into the completely cooled chocolate pastry cream to create a 'Creme Legere'.
- Always use a heavy-bottomed stainless steel or enamel saucepan. Aluminum or cast iron can react with the yolks and dairy, imparting a metallic flavor and turning the custard a greyish tint.
Storage
Refrigerator: 3 days — Keep covered with plastic wrap placed directly on the surface to prevent a skin from forming.
