What to do when T talks too much?

I didn't have a very good session with T today. It was our first session back after a long winter break and it was like she forgot about everything we had talked about the session before. Today, she just rambled on and on about mindfulness and I mostly sat and listened and nodded.
Now, I don't mind listening a fair amount, but it would have been more helpful today to talk more about how I have been feeling.
She must have realized at the end how much she had talked, because she said, "If you ever feel like I'm talking too much, just tell me to shut up!" But I don't want to tell T to shut up!
Is there a gentle way I can let my T know that I'd like to talk about something else or that she is rambling about something that isn't helpful?

"I'd like to focus on _____" It usually works.

It sounds good that she is open to being told to shut up! I like Kecanoe's suggestion, or you could also start the session by listing a few of the things you'd like to get through.

If you feel like it's hard to change the subject without being impolite, could you maybe thank her for whatever she's trying to tell you and then say that you want to make sure you have enough time to talk about X?

Channel stopdog and tell him or her to not talk anymore.

Somehow I feel SD's approach wouldn't work for me

I have the same problem sometimes and I find it really uncomfortable to be assertive enough to tell T, so I understand. But it is your time, and also T can't read minds so sometime like

'I'm really interested in the mindfulness stuff, and appreciate you bringing it up, thanks, but there's also quite a bit I need to cover after the break. Would it be ok to come back to mindfulness in another session so I get to cover both?'

I tune him out and try to look as uninterested as possible

I'd ask "excuse me, is this my session or yours?"

Maybe not, I've never had a rambling T, but I'd like to think that would be my response to one, because it would annoy and frustrate the begeeziz out of me...

How about discussing with T what a polite STFU would look like? It could be a code word or a signal, like when a preschool teacher puts her finger on her lips and (ideally) the class follows suit and falls silent...

Just an idea.

This has been a recurring issue with me too. Al of my ts talk too much and I have just begun to realise that they were teaching me something. To become more assertive. See I don't talk much and am naturally very quiet so that gives them some extra room to talk. I wish I could offer you some advice but I think it's a hard lesson to learn and it will keep coming into our life till we learn it. Your t seems very open to you giving her some more directions on how you would like your session to go. Do you think you could practise ways of being more assertive with her? I am sure she would be happy to experiment a little with this!

I don't have an answer for what to say when it happens; T has done it to me once or twice and I addressed it at the following session (it took me until after the sessions to realize what had happened and how annoyed I was). He was responsive.

That's a really good way to put it, thank you. I will try that if it happens again!

That's a great idea, since she is the one who says she talks too much, I could ask her how she would like me to tell her to stop! We are both very blunt with each other (which is how I like it) but I feel like just saying "STFU" is TOO blunt. So I could ask.

I agree, this is a lesson that happens outside of therapy too, and I will try to practice! I will try to bring this up next time!

I would look at him/her and say, "You know I am paying you to listen to me and if you continue to talk then I'm going to have to charge you," or "Does your talking mean I get a discount?"

Change your therapy orientation.

In any conversation that's one-sided and running long. I try to find a break and then just throw in "Well this is off the subject, but.." or "I know this is a non sequitur, but I'm hoping we can talk about "this" too."

In the past, I've put my hand out like a stop, then said I really have a few things I need to talk about today and don't want to run out of time. Then, I started each session by telling her what I wanted to work on and asked her to help me keep the session on track. That works fairly well for me. She still rambles occasionally, but I'm able to tell her that she's talking too much.

A previous t was a huge talker and I ended up quitting. Actually, I got up and walked out while she was talking and never went back. This was after my bringing up her talking too much and me not being able to work on anything in session, so she had a chance to change but didn't. Good luck