Heavy quarks created in heavy-ion collisions serve as an excellent probe of the produced quark-gluon plasma (QGP). The radiation pattern of jets formed from heavy quarks as they traverse the QGP exhibits a particularly interesting structure due to the interplay of two competing effects: the suppression of small-angle radiation, also known as the “dead-cone” effect, and the enhancement of emitted gluons by medium-induced radiation. In this , we propose a new observable, based on the energy correlator approach to jet substructure, which will allow us to disentangle the two scales associated to these two phenomena and to determine under which conditions the dead cone is filled by medium-induced radiation. Combined with the forthcoming high-statistics measurements of heavy-flavor jets, this work provides a novel tool to unravel the dynamics of the QGP. Published by the American Physical Society 2024