What you need
The whole thing is two ingredients most kitchens already have. Lynn starts by adding two-thirds of a cup of milk, which she points out is something nearly everybody keeps on hand, and then she melts five tablespoons of butter in a saucepan. She does not say on camera what kind of milk she is using, only that it is the milk already in the kitchen.
Equipment is just as short a list. There is the saucepan for the butter, a measuring cup for the milk, and a blender at the end if you want it whipped. Lynn uses her Ninja container for that part and pours the cooled mixture straight in, but she is clear the blender step is optional.
How Lynn makes it
She keeps the burner on a low medium so the butter barely melts. The point is not to cook the butter or get the pan real hot, just to take it to liquid. When she checks it, she shows that the butter is melted but nowhere near boiling.
Then comes the step that keeps the milk from curdling. Lynn brings the milk over to the stove and adds one tablespoon of the melted butter into the milk, slowly, then gets a little more out and adds that too. She explains she is tempering it so it does not mess the milk up.
With the milk warmed, she pours it into the butter left in the pan and lets the two start incorporating. She repeats that you do not want it real hot and you do not want it to come to a boil. It only has to get hot enough for the butter and the milk to combine.
Whipping it, or not
Lynn takes the pan off the heat and lets it sit and cool down for a few minutes. At that point, she says, you can use it as heavy cream right then if you do not want to whip it, which is the fastest route when it is going into a recipe anyway.
To make it look like what you buy, she pours the cooled mixture into her blender container and runs the blender until it whips up. She stops partway through to show that the butter has blended into the warm milk.
How much it makes and how she uses it
Lynn says the amounts she starts with should make around one cup of heavy cream. At the end she has a little over a cup and is honest that she did not get quite as much as she thought she would.
From there she uses it the same way you would use heavy cream in any recipe, and she mentions it would even be good in coffee for anybody doing the keto thing with butter in their coffee. She says that if you run out of it, you can make it yourself and not buy it at the store anymore for any kind of recipe. Her point through the whole thing is that you do not have to stop what you are doing and run to the store. The full walkthrough is on the video page, and if your kitchen throws you a curve you can always ask Lynn.