Marcus-Hush theory has long been recognized as the most successful attempt at developing a comprehensive model of electron transfer kinetics. It describes the electron transfer between reactants and products as a temperature-activated process governed by nuclear vibrations, energy reorganization, and electronic coupling. Several experimental confirmations of this theory have emerged since its inception in the 1950s, notably the observation of the so-called inverted region for intramolecular electron transfer and flattening of the exponential dependence of the rate constant on potential for electrode reactions. However, some intriguing predictions from the Marcus-Hush theory exist, which have not yet been observed experimentally. This includes the voltammetric behavior at inlaid microdisk electrodes, put forth by Feldberg, who predicted peculiar deviations of the steady-state voltammograms from the commonly-used Butler-Volmer model of electrochemical kinetics. Hexagonal boron nitride (hBN) is arranged into two-dimensional (2D) layers, in which boron and nitrogen atoms are covalently bound in an alternating hexagonal pattern, similar to graphene. These layers are held together by van der Waals (vdW) forces in bulk hBN. The lattice mismatch between hBN and graphene is only 1.5%, their bulk interlayer spacing is nearly identical (3.3-3.4 Å), and its polar nature renders hBN insulating, with a wide band gap of ~6 eV. These characteristics lead to an increased carrier mobility in graphene supported or encapsulated by hBN, owing to the atomic flatness, lack of dangling bonds, and suppression of charge doping at the graphene/hBN interface. It transpires from the present work that hBN is a suitable medium to study long-range electron tunneling, which leads to the observation of the Marcus-Hush behavior.