In my language, we have a word (a verb) for messy eating. When someone is eating messily, like when they play with their food, eat carelessly, or mess up their plate by making it look unappetising and gross, we say they are "balboocheh" (verb). This word is similar "muddle", "jumble" or "garble", except these words I believe don't really pertain "eating messily" (or perhaps they can be used so?).
In a sentence, the word should be used in this sense:
"Sara, stop [insert word]-ing your spaghetti. Eat properly!"