It's probably okay. She might have some diarrhea or throw up, but I'm sure she'll be fine. Are you worried about the lactose in the ice cream? It usually just makes cats a bit sick, but they recover quickly. Just keep an eye on her.
Its unlikely to do anything other than maybe give her a slight tummy upset. Lactose as a one off isn't a big deal, mint isn't an issue with cats and she's highly unlikely to have eaten any of the choc chips. Even if she did, I doubt the cocoa percentage in them was very high, and its a substance in the cocoa that is harmful.