We began our lunch with a half-dozen oysters on the half-shell. I was used to bland oysters from Washington and Massachusetts, which I had never cared much for. But this platter of portugaises had a sensational briny flavor and a smooth texture that was entirely new and surprising. The oysters were served with rounds of pain de seigle, a pale rye bread, with a spread of unsalted butter. Paul explained that, as with wine, the French have “crus” of butter, special regions that produce individually flavored butters. Beurre de Charentes is a full-bodied butter, usually recommended for pastry dough or general cooking; beurre d’Isigny is a fine, light table butter. It was that delicious Isigny that we spread on our rounds of rye.
Rouen is famous for its duck dishes, but after consulting the waiter Paul had decided to order sole meunière. It arrived whole: a large, flat Dover sole that was perfectly browned in a sputtering butter sauce with a sprinkling of chopped parsley on top. The waiter carefully placed the platter in front of us, stepped back, and said: “Bon appétit!”
I closed my eyes and inhaled the rising perfume. Then I lifted a forkful of fish to my mouth, took a bite, and chewed slowly. The flesh of the sole was delicate, with a light but distinct taste of the ocean that blended marvelously with the browned butter. I chewed slowly and swallowed. It was a morsel of perfection.
Read more here about Why Butter is Better.