Other forms found in the OED: palau, pillaue, pillow(e), pilo(e), polloe, pullow, pelo(e), pleo, pelaw, pilao, pillau, pil(l)aw, pellow, pillo(e), pillou, pilowe, poloe, poloo, pilow, pillao, pullao, pelau, peleau, polow, poolaw, perlau, perleau, perlew, perlo(o), perlow, purloo, pearlo, pilav, pillaf(e).

But "pilaf" (based on the Turkish form) is the spelling I grew up with.