K: Here, eat this.
B: What is it?
K: I'll tell you later, have some.
(a few bites later)
B: Um, do you want the rest of this? Because I don't like it very much.
K (disappointed): Really? I quite like it.
B: No, I don't. What is it anyway?
K: It's bird's nest soup. Why don't you like it?
B: Not what you call it, what is it?
K (frowns): It's a bird's nest soup.
B (somewhat afraid): What's it made of?
K: A bird's nest!
B: No, I don't like it.
If you ever have the opportunity to try a sample, politely decline.