Chocolate Pastry Cream Recipe

In a large bowl, set up an ice bath by partially filling it with a combination of cold water and ice. Set aside. In a 2-quart stainless steel saucier, whisk together sugar, cornstarch, salt, and cinnamon. Whisk in egg yolks, followed by the milk, until well combined. Cook over medium heat, whisking constantly, until pastry cream begins to thicken, about 8 minutes. Once it thickens, continue to whisk, pausing every few seconds to check for bubbles, about 1 minute. When it begins to bubble, set a timer and continue whisking for 1 minute. This step is important to neutralize starch-dissolving protein found in egg yolks. Off-heat, whisk in chocolate, butter, and vanilla extract until chocolate and butter have melted and all ingredients are thoroughly combined. Strain pastry cream through a fine-mesh strainer set over a medium heatproof bowl. Immediately place plastic wrap or buttered parchment paper directly on the surface of the cream to prevent skin from forming. Transfer bowl to prepared ice bath to chill for 30 minutes, then refrigerate until cold, about 2 hours. When you are ready to use the pastry cream, whisk until smooth.