The exothermic continuous stirred tank reactor (CSTR) is a classical yet complex case study of nonlinear dynamical systems. Power-shaping control is a recent approach for the control of nonlinear systems based on the physics of the dynamical system. In this paper we present a general methodology to apply the power-shaping control approach to the exothermic CSTR study case. It results in a global Lyapunov function for the exothermic CSTR. This Lyapunov function is then reshaped by the means of a controller in order to stabilize the process at a desired temperature. Some considerations on the local and global convergence to the desired state are presented.