Discipline doesn’t work 😐

Ok, maybe I’m just clueless, but daughter (1.6 years old) does NOT take me seriously. For some reason when she doesn’t want to eat anymore, she’ll just start spitting the food out. It gets everywhere - on her clothes, my clothes...MY FACE. (We don’t let her eat out at restaurants bc we know the havoc she’ll cause lol). It frustrates me so much, and when I firmly tell her “no, no” and give her my mean face, she just spits more. She looks me dead in my eyes and spits even harder. I give this child so much positive reinforcement/attention, so I don’t understand why she wants negative attention. Please help me lol