For a quality lunch, pay a visit to the Museum Brasserie, which is in the Museum of Fine Arts overlooking the Palace Royale. It has a menu terroir of Belgian cuisine cooked by the Michelin-starred chef Peter Goossens.
www.museumfood.be
Rue de la Regence 3, 1000 Brussels
Google map: tinyurl.com/njs39t
Overlooking the Place Royale (Royal Square - and square it is). Not overlooking the Royal Palace (Palais Royal), which is on the other side of this Place Royale. In front of the Parc de Bruxelles. But for real food and atmosphere, just walk to the Place du Sablon nearby.