Step 1: Scald the milk - Time 3-7 minutes
First you have to scald/pasteurize your milk. This means pouring 4 cups of milk into your saucepan and, over high heat, bring it almost to a boil. This will take about 3 minutes if the milk is at room temperature or 5-7 minutes if it’s just out of the fridge. As the milk is just starting to bubble around the edges of the saucepan, remove from the burner. Put a lid on the pan if you want, and then walk away.
You also have the option of adding the powdered milk now, and whisking it in, or doing it later. It doesn’t matter.