I would not describe that as CBT. A CBT therapist works on your cognitive distortions and negative though patterns; they're not taught to be "sarcastic" and make fun of the client. It sounds like that might just be a personality characteristic of your T? There is no treatment modality that encourages sarcasm and making fun of the client!! Honestly, that just sounds like a style thing to me.

HOWEVER....if you don't feel that it is a good fit, you have a right as a consumer to work with a therapist whom you feel comfortable and safe with.