Start by putting the cream, butter, and sweetener into a shallow pan (like a frying pan or skillet).
Stir until dissolved and bring to a boil on medium to high heat.
Once boiling, simmer, stirring occasionally until condensed by about half and thick and bubbly.
Should take about 15-20 minutes.
This will make about a cup to a cup and a half of sweetened condensed milk. And now you are ready to make fudge! (This cream can also be used as a yummy coffee creamer.)