Based, obviously very loosely, on this recipe.
1/2 cup cocoa
12 drops sucralose
12 tablets saccharin
4 egg yolks
2 cups whipping cream
1 tsp. vanilla
Heat 3/4 cup cream to a simmer. Meanwhile, whisk the yolks with the cocoa, the salt, and the sweetener. Slowly whisk the cream into the yolk mixture. Return the mixture to the pot and cook on low, whisking constantly, for a few minutes until it thickens. Scrape the mixture into a covered container and refrigerate until cool.
Beat 1 1/4 cups cream with the vanilla until soft peaks form. Fold the cream into the custard. Refrigerate.