Combine Ingredients: In a medium saucepan, combine milk, sweetener, and butter (if using).
Simmer: Heat over medium-low, stirring frequently, until the mixture thickens and reduces by about half (20–25 minutes).
Cool: Remove from heat and let cool. The mixture will thicken more as it cools.
Store: Transfer to a clean jar and refrigerate for up to 1 week.
Tips:
Stir constantly near the end to prevent scorching.
Use in coffee, desserts, or recipes that call for condensed milk.
For extra flavor, add ½ tsp vanilla extract during simmering.
