In contemporary internet and Gen Z slang, saying "she's cooking" means that a woman or girl is doing an exceptional job, executing a brilliant strategy, or producing impressive, high-quality work. Stemming from the viral phrase "let him cook," it highlights a moment where someone is showcasing their talents, creativity, or intelligence with great success. Whether she is acing an exam, delivering a stellar presentation, or creating amazing art, it serves as high praise for her outstanding performance.