Try this Rich Chocolate Pudding recipe
Starch-thickened puddings fail when cooks stop heating before the interior network of starch molecules reaches its full gelatinization point. Raw starches release water prematurely, causing the chilled dessert to separate into a watery pool beneath a firm skin.
Watch the surface movement and coat the back of a spoon to judge doneness accurately. Simmer the mixture until distinct bubbles break sluggishly on the surface rather than rolling rapidly. Draw a clear path through the cream coating on a metal spoon with a finger; the liquid should hold that defined channel without immediately running back together. This precise physical resistance indicates that the starches have absorbed maximum liquid and built a stable matrix.
Scorching represents the primary hazard during this stage. Keep the heat at medium-low and use a flat-bottomed silicone spatula to sweep continuously across the base of the saucepan, preventing cocoa solids from burning against the metal. Incorporate bittersweet chocolate and unsweetened cocoa powder gradually to build depth without introducing bitterness.
Cover the surface directly with plastic wrap pressed flat against the warm dessert before refrigeration to prevent a tough skin from forming during the cooling process. Chill the containers for at least four hours to allow the fat globules in the whipping cream to solidify fully.