1-Begin by whisking the egg yolks and cornstarch together in a heatproof bowl until they form a thick mixture, adding a few drops of milk if it feels too stiff. In a saucepan, warm the milk and sugar over medium heat until the sugar dissolves and the mixture starts to simmer, then take it off the heat. Slowly add this warm milk to the egg mixture while whisking to temper the eggs and keep them from scrambling.

2-Next, strain the combined mixture through a fine sieve back into the saucepan to remove any bits. Return it to medium heat and whisk constantly until it thickens and you see boiling bubbles, which takes about 1 2 minutes. Stir in the butter, vanilla extract, vanilla bean seeds, and salt right away.

3-Cooking and Chilling Steps: 1. Let the mixture cool for 10 minutes before covering it with plastic wrap directly on the surface to prevent a skin from forming. 2. Refrigerate for at least 3 hours or overnight to set properly. 3. For vegan options, use plant-based milk and thicken with extra cornstarch instead of eggs.