Method for forming large-dimension ceramic tiles comprising the following operative stages: feeding a determined quantity of powders into the mould cavity of a first pressing station; pressing said quantity of powders to obtain a slab of congruent material the thickness of which is reduced by a quantity between 20 and 40%; feeding said slab to at least one decorating station which deposits in a controlled manner at least a second layer of powders; feeding said decorated slab to a second pressing station; pressing the decorated slab.