Why was the puree in Soviet canteens so weightless, even when milk was in short supply?
The answer is simple: our grandmothers knew a secret that modern chefs have forgotten.
All you need to do is replace milk with an ingredient that is in every home. And it is not water.

The main secret is the broth in which the potatoes were boiled. Do not drain it!
While the potatoes are hot, mash them, gradually adding 3-4 tablespoons of this starchy broth. It acts as a natural thickener, making the puree smooth and airy.
But there is a nuance: the potatoes must be of a crumbly variety, for example, “blue-eyed”.
If the tubers are too watery, add a spoonful of potato starch - it will compensate for the lack of texture.
The second life hack is vegetable oil. Yes, it will replace butter. Whisk the puree, pouring in 2-3 tablespoons of sunflower oil in a thin stream. This will give the dish shine and lightness, and the taste will remain neutral.
For a piquant twist, add a pinch of nutmeg or a teaspoon of mustard - this is what they did in student canteens to "revive" the bland puree.
And finally: never use a blender! It will turn the potatoes into a sticky mass. Only a masher or a regular fork.
And if you want something more sophisticated, pass the puree through a sieve - a method that was used in Soviet restaurants for special guests.
Now you know how to return the puree to that same “Soviet” tenderness without a gram of milk.