I'm two for two on trips to Brussels and eating mussels while there. Much like eating chocolate or eating waffles, you can't go to Belgium and not order yourself a big pot of mussels at least once. It's impossible to walk the streets of Brussels near the city center and not walk past restaurant after restaurant begging you to stop in and enjoy their mussels. With hardly any effort at all, I devoured the whole pot below, the frites, and a Belgian beer, of course.
If you know of a place that has great mussels, please fill me in!