Add milk, cream, and sugar to a small saucepan and heat over medium. Whisk to combine and dissolve sugar. Bring to a boil.
Turn heat down slightly so that mixture is at a gentle boil / strong simmer. Cook to reduce, checking on it and whisking it often. If it starts to boil over, give it a whisk, but don't turn down the heat too much. Keep the heat at medium/medium low, but closer to medium. You need the heat to reduce it.
Once the mixture is thick and creamy, add vanilla extract and whisk to combine.
Pour into a small mason jar or bowl and let cool before using.
Video
Notes
YieldApproximately 7 oz if left to reduce for about 40-45 minutes. This is about 1/2 of a large Eagle brand sweetened condensed milk. Doubling Batch If doubling to get a full 14 oz, I would suggest making two batches, instead of doubling in one pan. This will keep the total cook time about an hour. StoringFridge: Store in an airtight container in the fridge for up to 1 week. Freezer: Store in freezer in a freezer-safe container for up to 3 months. Thaw in the fridge overnight before using, whisk to combine if it separates. Substitutions:Milk: You can also substitute up to 1/2 cup of 2% milk for whole. Sugar: You can substitute honey for the sugar, although it will make for a much darker, golden-colored condensed milk.