Essence of Tomato Prepared with Canned Tomato Puree

Read the list of ingredients on the puree you buy: The puree should contain nothing but tomatoes and citric acid. The finished essence will have turned orangy red by the time it has finished baking. It is up to you to judge whether it needs thickening or not. If it does, prepare a slurry of potato starch and thicken as indicated in the recipe above.