Uganda's northern shea trees produce "Nilotica" shea butter, a softer, lower-melting-point variant valued differently from the West African shea butter more familiar internationally.
Moo yaa is butter pressed from the nuts of the shea tree that grows wild across Northern Uganda, traditionally served alongside dek ngor so the two together make up a complete Acholi meal.
Why it's made this way: As ghee is to the cattle-keeping Banyankole in the west, moo yaa is to the Acholi — a prized fat that also carries ceremonial weight, offered to in-laws during marriage negotiations as a sign a bride can cook for her new family.