A process for preparing an intimate mixture of uranium (or mixed uranium-plutonium) oxide and carbon was investigated. The objective was to obtain a starting material for carbide or nitride fuel material by a carbothermic reaction between carbon, uranium (plutonium) oxide, and nitrogen. These materials are attractive as nuclear fuel materials because of their high thermal conductivity and fissile material density, but suffer from the high cost of production. The process studied, which involves the rapid calcination of a mixture of uranium nitrate and sugar, would potentially lower the cost because (a) it would avoid forming the metal, and (b) it would eliminate the necessity of several steps heretofore required to thoroughly mix reactants for a carbothermic reaction.