  We study the fully nonlinear time evolution of a holographic system
possessing a first order phase transition. The initial state is chosen in the
spinodal region of the phase diagram, and includes an inhomogeneous
perturbation in one of the field theory directions. The final state of the time
evolution shows a clear phase separation in the form of domain formation. The
results indicate the existence of a very rich class of inhomogeneous black hole
solutions.
