A method for producing a cup for a capsule for the preparation of infused or soluble beverages is provided. The method includes the steps of co-injection molding a cup of multilayer plastic material with an intermediate layer of the gas barrier type, the cup being a single body provided with a bottom having a nozzle, and an inner base including a completely closed central portion covering the nozzle, partially cutting the central portion to form at least one opening connecting the inside of the cup and the nozzle, and a further step of folding a portion of the cup between the opening and the nozzle towards the inside of the nozzle to form a deflector.