I had a with my best friend and I am curious if she may want to expirament some more, just us 2...?

Don't 'get her drunk' for the purpose of taking advantage of her. What actually might work out better for seeing if she's interested is for -you- to drink a little, or pretend to get drunk ;) and then mention to your friend how hot the was and see how she reacts. If she's horrified, you can blame it later on being drunk - if not, -then- you can 'go at it'.