Can you identify the two key ingredients when making Haggis?

Haggis is Scotland's national dish, and it's a savoury pudding traditionally made from sheep's pluck – that's the heart, liver, and lungs. Now, while those might be the more *unique* ingredients, they're not the *key* ones we're looking for in this question. The mixture is minced with onions, oatmeal, suet (animal fat), spices, and stock, and traditionally encased in the animal's stomach and simmered. So, while the offal is certainly distinctive, the onions and oatmeal are absolutely essential for the flavour and texture. The oatmeal gives it that characteristic nutty, slightly chewy consistency, and the onions provide a crucial savoury base. Without these two, you simply wouldn't have haggis! Chicken and dough are ingredients that you may find in other types of food, but not in Haggis.