Numbers: Using Principals of Art and Design When designing a dish, the theory of numbers keeps it from looking chaotic. This is a visual concept. It is used to compose single and mixed dishes and in meal composition. A single dish has one majorprimary element and the possibility of decorativeingredients. A mixed dish combines more than one primary element (usually vegetables) they should be of equal amount and not more than 7-9 in a dish. Usually odd numbers are best. However, by using something from the onion family the dish may either count this ingredient or not. In meal composition, the focus may be single, such as chili over cornbread with a side salad, or multi-focus such as soup, salad, braised bean/seitan roasted squash, and rice pilaf.