Methods of controllably forming Bernal-stacked graphene layers are disclosed. The methods comprise: (1) cleaning a surface of a catalyst; (2) annealing the surface of the catalyst; (3) applying a carbon source onto the cleaned and annealed surface of the catalyst in a reaction chamber; and (4) growing the Bernal-stacked graphene layers on the surface of the catalyst in the reaction chamber, where the number of formed Bernal-stacked graphene layers is controllable as a function of one or more growth parameters, such as a total pressure of the reaction chamber. Further embodiments of the present disclosure also include steps of: (5) terminating the growing step; and (6) transferring the formed Bernal-stacked graphene layers from the surface of the catalyst onto a substrate.