A good choice for lunch on the Grand Place is 't Kelderke (The Little Cellar) - a restaurant with great atmosphere and food.
The restaurant is built into an ancient cave and serves dishes which are typical of the region.
Soup is a very reasonable 2.25 euros, and moules marinieres, 6.25 euros. My wife had the pot-au-feu, and I chose carbonnades flamandes a la biere, both of which were delicious and priced at just 4.75 euros each.
We drank an excellent beer from tap. 't Kelderke was superb value for money in truly authentic surroundings.
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