I need advice with a message on facebook. Im not planning on picking up random people etc.

Around the beginning of this year (My AFC days), when I started to learn it proper, I was hanging out with few mates. One of my mate (Another PUA, much more experienced) used to bring out his gf and her mates with him. There was one of her female friends who we used to flirt etc, but she had a serious bf relationship (ie living together in the same house)

Because my mate broke up, we never ended up hanging out anymore, saw her occasionally in town where she work as I was shopping but that was about it.

Now the question
Recently she broke up with her bf, what would be the best way to just ask her out for a drink etc.