Perhaps others make equally good frittes but this is THE Place! I recommend it even though you may have to queue for a short while and there are no seating… Well, just bring your cone of frittes (large I would get, and you feel full for a long time ) and walk to one of the adjacent bars and sit down, order a Trapist Belgian Beer and enjoy! Only avoid the few bars with “frittes not allowed signs”. A myriad of sauces to choose among, wil take you a year or two to try them all!
For the tourists hanging around Grand Place, yes, this is not so close. But it is a chanse to get out of the center and visit the EU quarters, the cinquantenaire park etc.