Although it's also done for team-building business entertainment, there are chocolate-crafting evenings. Have you looked for any Michelin stars in Belgium?
Pandemic and time-passed warnings, but we enjoyed a (French beef) steakhouse in Turnhout called Bistro het Meulderke. And an expense account place, Savoury. There was a high-end restaurant in Antwerp, on a real medieval courtyard, with a name like Sir Anthony Van Dyke. The lavish Sunday Brunches at the Antwerp Hilton are popular. Mussels are pretty reliable in Belgium. Haven't been in ten years. There was a touristy Belgian place in a medieval cellar in Antwerp, with trestle tables, and other cellar restaurants like Roji Sushi. I'm sure it has turned over, but the Caribbean Inn was located in a neat deconsecrated chapel called St. Anna Godhuis.
The reopening of the KMSKA museum in Antwerp may have stimulated new restaurants in an attractive, historic neighborhood? Also the two previous museum openings, Red Star Line and MAS.
Edit: It has to be the case that the European Parliament supports an infrastructure of expense-account restaurants in Brussels. But I don't like the city enough to go there much. And it has to be noted that the picturesque Rue des Bouchers has a long reputation for dishonest pricing and unwanted supplements. I have only eaten on Bouchers once (20 years ago), and although I was seated by a tout, I was not cheated. Perhaps it's because he learned that I could speak French.