When it comes to purees, texture is the focal point. Sure, flavor remains important, but purees are meant to be smooth and silky with a consistent texture throughout. It’s well known that an immersion blender is the ultimate tool for incorporating all ingredients for a puree and that chickpea flour helps soup develop a velvety finish, but these aren’t the only tricks that help create a smooth puree. Whether making a creamy potato leek soup or applesauce on the stovetop, you’ll want to monitor how much water is evaporating, and if the thick liquids are cooking evenly. Instead of using a metal lid to regulate all this, consider using a cartouche.
A cartouche is a lid made from parchment paper; in the United Kingdom, the same word also refers to a piece of parchment paper that’s used to line baking pans. To better understand its purpose, Chowhound spoke to Lance Knowling, the executive chef at Northridge Restaurant, who explained, “A cartouche is required for removing the water from a particular item like a puree of some sort that needs to slowly cook to remove moisture, and concentrate the flavor.”
Cartouches are used because metal lids often cause a thick skin to form on top of the puree. A cartouche can stop this unwanted top layer from forming as it prevents the surface from coming into contact with air. Aside from purees, it’s also useful for making stews, soups, and sauces. Slow cooking, braised meats, and poached fruits can also benefit from this French technique.
How to make a cartouche
A cartouche is intended to be a single-use item, so you’ll need to make a new one each time. All you need to make one is a pair of scissors and some parchment paper. According to Lance Knowling, there are two ways to make a cartouche: “There is a way to fold parchment paper to create a perfect cartouche or you can measure the inside diameter of the pan or pot and cut it out with scissors … this is much faster.”
For the former method, start with a square piece of parchment paper slightly larger than the pot or pan. Fold the paper in half, and then in half one more time to form a smaller square. Then, fold to create a triangle. Continue folding until the paper has a narrow triangular shape. Find the center of the pot, hold the tip of the triangle over it, and trim the outer edge of the triangle so that, when it is unfolded, it forms a perfectly fitting circle.
Regardless of how you make your cartouche, it is vital that you do not forget the final step. Knowling reminds us, saying, “Don’t forget to put a small hole in the center! I usually do this by eye, but I’ve been doing it for a while.” This can be done while the cartouche is still in a triangle shape (cut a small hole or notch at the tip) or, if you are using Knowling’s second method, after you have cut the cartouche out. Remembering to make this hole is vital as it allows some steam to escape while the puree is cooking. When ready to use, lay the cartouche directly on top of the puree and let it work its magic.
