In order to make a granulated substance (G) of an aerated foodstuff, such as granulated meringue, said substance having an outer surface that appears continuous to the naked eye, an alveolar (18) structure (12) is provided, and a liquid precursor of the aerated foodstuff (for example, the so-called "meringue foamed mixture" in the case of meringue) is introduced (20, 22) into the cavities (18) of the structure. Consolidation of the precursor introduced into the cavities (18), obtained, for example, via heating (24), leads to the formation, in the aforesaid cavities (18), of respective particles of granulate (G), which are finally extracted from the cavities (18), typically exploiting the deformation of the material constituting the alveolar structure.