Cooling of chocolate coated products requires cooling tunnels with optimal settings according to product and chocolate properties to get the desired quality with respect to surface gloss and hardness of coating. The author proposes a model for the calculation of the bulk crystallization and temperature variation within the coating during cooling. The model is based on one-dimensional, unsteady-state hear transfer accounting for internal heat generation by crystallization. The latter is assumed to be a function both of current temperature and non-crystallized material. Simulations of cooling of coated cookies under different cooling conditions in a two-step process using the model show possibilities for optimizing the process with respect to expected surface gloss and hardness.