Condensed milk is expensive if you buy it, and it gets used up in the blink of an eye, so I decided to make it myself. There is absolutely no difference between using discounted milk that is close to its expiration date and high quality milk, so it's a great deal. I use a 1 L container of milk when making this, and store it in the freezer.

Be sure not to let it burn when mixing and reducing the milk.
If you use white sugar, it will be slightly cream-coloured, but if you use raw sugar or brown sugar, it will have a slight amber colour. Choose whichever you like.
You can also use soy milk, by the way. Recipe by Takobasu kitchen