Mix dry ingredients with 100 ml of milk and mix to dissolve everything. Add rest of milk, bring to a boil over medium heat while stirring constantly. If you're worried about lumps, blend it with a hand blender when it's warm enough that the chocolate has melted.
After it's thickened and starts to bubble up, pour into your serving cups or bowls, don't cover unless you're some weirdo who doesn't like skin, and let cool then put in fridge for at least 4 hours to cool down completely.
Eat and repeat.