  We have constructed a class of perturbative dynamical black hole solutions in
presence of cosmological constant. We have done our calculation in large number
of dimensions. The inverse power of dimension has been used as the perturbation
parameter and our calculation is valid upto the first subleading order. The
solutions are in one to one correspondence with a dynamical membrane and a
velocity field embedded in the asymptotic geometry. Our method is manifestly
covariant with respect to the asymptotic geometry. One single calculation and
the same universal result works for both dS and AdS geometry or in case of AdS
for both global AdS and Poincare patch. We have checked our final answer with
various known exact solutions and the known spectrum of Quasi Normal modes in
AdS/dS.
