  Incompressible 3D Euler equations develop high vorticity in very thin
pancake-like regions from generic large-scale initial conditions. In this work
we propose an exact solution of the Euler equations for the asymptotic pancake
evolution. This solution combines a shear flow aligned with an asymmetric
straining flow, and is characterized by a single asymmetry parameter and an
arbitrary transversal vorticity profile. The analysis is based on detailed
comparison with numerical simulations performed using a pseudo-spectral method
in anisotropic grids of up to 972 x 2048 x 4096.
