Melt the butter in the pan over LOW heat. The butter will boil and foam. Listen carefully, you will hear the butter boiling. Once the moisture has boiled off, the pan will be very quiet. Once quiet, the carmelization will happen very quickly.
Continue cooking the butter until the milk solids begin to turn golden brown. It is best to not rush this process because once it starts to turn brown it can quickly go too far and taste burnt.
Once the milk solids have browned, remove the pan from the heat and stir the cream into the butter. If you are using sweetener, add it along with the cream. The cream will foam and bubble initially but will then stop. Return the pan to medium heat and allow the cream to come to a full boil. The cream and the butter may look separated, but keep stirring! A whisk works well.
Continue cooking until it has thickened and feels “sticky” (The bubbles will take longer to come to the surface).
Remove the caramel from the heat, continue to stir until it begins to cool. If you let it sit while it is hot, the butter and cream may separate. Continue to stir it for a few minutes and it will hold together as a thick sauce. You can pour it into candy molds at this point if you wish.
Enjoy the caramel served warm with your favorite keto dessert! If you cool this in the refigerator, the caramel will become solid and makes great fat bombs.