There is one substitutions I use for recipes that call for double cream; however, you can’t make double cream in its natural form unless you have a cow. Double cream contains 48% butterfat and is something we don’t sell here in the United States. The closest we come is 40% butterfat with heavy whipping cream. You can get a higher fat content for your recipe by combining 2 tablespoons of buttermilk with 2 cups of heavy whipping cream. Heat to 98 degrees, then place the mixture in a glass bowl in a warm place until it thickens. Line a wire strainer with 3 layers of cheesecloth, place over a bowl, and fill it with the mixture; place it in the refrigerator. The whey will drain into the bowl and you will be left with the cream. This is the only substitution I know of for double cream.