She's certainly not adjusted to the new baby - she might be used to her being there, but the baby's needs and behavior are changing so it is a constant adjustment for the older child. What she does notice is that the baby gets (and should get) immediate response from you. So she's not about to respond immediately to your requests! The baby kind of "controls" you (from your daughter's vantage point) so your daughter wants to do the same thing!
You should try to have special one-on-one time with her, do some big-girl things, whether that's when the baby sleeps or when your husband is home.
Some kids have trouble transitioning from one activity to another, so it is reasonable to give her a warning when you can - "In 5 minutes (or when the TV show is over) it will be time for us to go to the store" or "time to pick up toys and have dinner." If it's going to be more than 5 minutes, then give a 2nd warning. Then stick to that time frame.
Otherwise, you need to try 1-2-3 or other method - but whatever you choose, stick to it! Take away something really important to her (but it must be immediate) or put her in time out. Taking her away from what she is doing is probably the best thing. Then implement a sticker chart or other incentive program.
You are the parent and she can't be controlling you. Be specific about what you object to - "being mean" might be too vague for her, but saying "I don't like it when you stick your tongue out" is more effective and precise.
Good luck.