- 2/3 cup sugar
- 2 tablespoons cornstarch
- 1/2 teaspoon salt
- 1 large egg plus 1 large egg yolk
- 1-1/2 cups heavy cream
- 2 tablespoons unsalted butter
- 1 teaspoon vanilla extract
- 6 ounces blackberries, mashed (3/4 cup)
- Whipped cream, for serving
- Whisk together the sugar, cornstarch, salt, egg, and egg yolk in a medium saucepan. Whisk in the cream.
- Cook over medium heat, stirring continuously with a wooden spoon, until thickened and steadily boiling, 8 to 10 minutes. Remove from heat and stir in the butter and vanilla until the butter melts.
- Divide among serving bowls or glasses. Spoon the blackberries on top. Cover with plastic wrap and refrigerate until well chilled, at least 1 hour and up to 2 days.
- Serve topped with the whipped cream.