Well, churros probably are involved.
Until Europeans (the Spanish) arrived, the natives had no cooking oils, no sugar and very little animal protein, particularly in certain more barren parts of the inland Americas. Sheep, cattle, domesticated goats and draft or transportation animals such as horses were all brought by the Spanish.
Indians weren’t immediately able to adapt to this change in diet, although I suspect that it was really the change to a sedentary lifestyle in the 20th century that did them in.