The invention relates to a method for preparing a composition essentially including a compound containing vanillin and ethylvanillin. The method for preparing a composition essentially including a compound containing vanillin and ethylvanillin according to a vanillin/ethylvanillin molar ratio of 2 is characterized in that it includes an operation of co-granulating vanillin and ethylvanillin at a temperature of between 50°C and 57°C in the form of a powder and in amounts such that the vanillin/ethylvanillin molar ratio is at least equal to 2, and an operation of lowering the temperature of the composition thus obtained to room temperature.
