In control: The first dynamic one‐pot three‐component asymmetrictransformation between aldehydes, protected α‐cyanoglycine esters, and enals catalyzed by a combination of a simple hydrogen‐bond‐donating catalyst and a chiral aminecatalyst is disclosed. Polysubstituted proline derivatives, which have a quaternary α stereocenter, were synthesized with high endo‐, diastereo‐, and enantioselectivities