https://www.allrecipes.com/recipe/282453/5-ingredient-vegetarian-chili/

This recipe calls for a diced onion as well as canned items. You could use frozen diced onions if you prefer. For one person I find I waste food, so I try to minimize that. If you are diligent and don’t use the entire onion for a recipe, you could dice the remainder and freeze it in a freezer bag/container or purchase already diced frozen onions. Either way, waste not-want not.