This term had many spelling variants, including rasho, richot, rouchou, rousseau, rusho(o), rowshow.
1848  They call it richeau; it is uncommonly rich, and very little will suffice for an ordinary man.
1879  He labors hard now in the river's bed,/Enjoying his three square meals a day,/And getting fat on richeau, spuds, and bread.
1914  . . . the other was called by the plain hunters a "rechaud." It was cooked in a frying pan with onions and potatoes or alone.
1938  While the white man was making a fire of buffalo chips and preparing a meal of richeau, the Indian . . . wandered far afield. . . .
1963  When flour was procurable, the trippers disintegrated the solid pemmican in a frying pan by heat, added flour, pepper or salt, and made a dish fit for the gods called locally "Rushoo". . . .