Bring the milk to a boil with the sugar and cinnamon stick in a large, wide pot.
Dissolve the baking soda in a little lukewarm water and carefully pour it into the hot milk (it will foam, so keep the pot over high heat to prevent it from boiling over).
Lower the heat and cook, stirring constantly, for 45-55 minutes, until the milk thickens and turns a golden brown caramel color.
Remove the cinnamon stick and season with a pinch of salt.
Pour into a jar, store in the refrigerator, and serve spooned over bread, pancakes or fruit.
A Receptnaptár original recipe. Calories and protein are estimated.