Moules Frites (or Mosselen met Friet in Flemish) combines the most beloved products of the Belgians—mussels and fries. This dish is easy to find in any café or restaurant all over the country. As a rule, mussels are steamed in white wine mixed with shallots, parsley, and butter. But there are numerous variations of the sauce—it may be based on beer, cream, mustard, include celery, leeks, garlic, etc. Moules Frites is said to go best with a wheat beer. Sometimes, mussels are served separately, without fries. In such cases, they're considered an appetizer or snack.
The funny thing is that mussels are imported from the Netherlands. Today, the mussels farmed in Belgium fail to satisfy demand. Every year, around 3 million tones of mussels are brought from the Netherlands—that is roughly 3 kg (6,6 lb) per Belgian. The Dutch mussel season is mid-July to mid-April. Outside of the season, some mussels are imported from Denmark, but the latter are less praised.