If she approaches you in a similar situation, asks/demands something, pause, look her straight in the eye and say Good Morning/Afternoon, and pause seeing if she will respond in like. Or, How are you this morning/afternoon. Keep direct eye contact and wait for her response.
If she drops off another "job" look her right in the eye and say, You're Welcome. In other words, don't stoop to her level and slam her with kindness. May or may not work but you know you are being the nice person.