Short facts : It adds richness and creaminess to a dish

Crème épaisse is a cultured and fermented dairy product with a thick consistency and a high fat content, typically 30–40%+. It is commonly used in French cooking for sauces, soups and toppings due to its stability under heat, as it will not curdle when heated, unlike lighter creams. Crème épaisse is a luxurious ingredient that adds richness, creaminess and a touch of sophistication to any dish.

Crème épaisse is not to be confused with sour cream which is generally more sour and lower in fat procentage. As substitute you can use double cream or even mascarpone.