That's right, forget about the movies where you see the whole dinner already prepared, candles freshly lit, and you're wearing a clean, lint-rolled v-neck sweater that was recently purchased from J-Crew. Maybe that should happen once or twice, but for me, cooking should be interactive and done together. Put some light snacks/hors d'oeuvres out and maybe do some prep work*, but try to cook with her. Include her. It shows that you two can work together somewhat successfully. It'll become more personal and less Japanese Steak House.
*Do the "gross" prep work before she arrives - trim the fat off chicken, de-vein shrimp, de-beard mussels, etc.