I have attempted this before and delivery seems to be the most crucial part. Saying something like "Whenever we talk you get all nervous cause you're trying to impress me" with a slight smile stuns a woman and usually merits her getting even more flustered and playfully hitting me in the arm.

Some other flirty call-outs that might work are:

"Wow it's pretty obvious how much you desire me."

"It's cute when you try and pretend that you don't want me as bad as you do."

"Aww someone's been missing me."

What do you all think about this topic? Please share your thoughts.