Heat a heavy bottomed deep pan. Add milk

Add sugar into the pan

Heat in low heat and stir until Sugar has dissolved

Once all sugar is dissolved bring mixture to a simmer over low/medium heat. Don't stir once mixture starts to simmer or it will crystallize or crack. Milk will darken to almost grey, reduced by half and thickened.

If you notice some form forming at the top, gently skim it off with a spoon. Make sure they do not drop back into the milk

Gently simmer for 35-40 minutes

Remove and pour into a glass jar. It will thicken further and turn a creamy yellow once it cools