Ok (am I the only woman on this thread?) here's my approach.
Say ok, you understand. No pressure. No furrowed brow. Use your best Sensitive Man face.
Come back and have the beer a couple more times. Talk about how you like it. Don't get smarmy. Say something technical, like how you think it might be the early additions of the X hops that really make this beer, and does she have any suggestions for brewing something like it?
Pro tip: do not hint that you think you can improve on her recipe or brewing technique.
If she doesn't give you the recipe, move on. You've already stated to us (and perhaps to her, if she reads boards) that you don't think it's superlative; in a world with great recipes, you believe you can find better. Likewise, she may be holding out with whom she shares her recipes.