Cook the custard: Pour the tempered egg mixture back into the saucepan. Cook over medium-low heat, stirring constantly with a spatula, until the custard thickens and coats the back of the spatula. The temperature should reach about 170°F (77°C). Do not let the custard boil.
Step 2: Strain and Chill the Custard
Strain the custard: Remove the custard from the heat and strain it through a fine mesh strainer into a clean mixing bowl to remove the vanilla bean pod and any cooked egg bits.
Cool the custard: Allow the custard to cool to room temperature, then cover the bowl with plastic wrap and refrigerate for at least 4 hours, or overnight, until it is thoroughly chilled.