This is a great technique: you mix language exchange with cultural exchange (learning to prepare non-Chinese food). I agree with your "old school": same-sex exchanges prevents a lot of unnecessary problems.
So which are your favorite sites for finding language partners?
I normal go on FB as there are a couple of local groups there. I google once and I think there was one call languageexchange.com or something like that. I registered my details, and every now and then I get requests from all over Taiwan even though I specifically said I was only looking for F2F with girls in Taichung