Everything is elementary simple. In the same way as it is done with cheese. I take at the rate of 1 liter: I made 400 ml, the cheese yield turned out to be about 125-150 grams, i.e. there is enough cream for a good roll.
Preheat the cream to about 80 degrees, add lemon juice or citric acid diluted with water, warm it over low heat for 10 minutes.