Julia Child's Biftek Haché à la Lyonnaise

"Shock is the reaction of some Americans we have encountered who learn that real French people living in France eat hamburgers," writes Julia Child in "Mastering the Art of French Cooking." Shock was also the reaction when I found a hamburger recipe in her seminal cookbook. Even though the burger is more than a little fussy, it satisfies in an elegant way.

¾ cup finely minced yellow onions
2 tablespoons butter
1 ½ pounds lean ground beef
2 tablespoons butter, softened
1 ½ teaspoons salt
1/8 teaspoon pepper
1/8 teaspoon thyme
1 egg
½ cup flour, spread on a plate
1 tablespoon butter and 1 tablespoon oil
½ cup beef stock, canned beef bouillon, dry white wine, dry white vermouth or red wine
2-3 tablespoons butter, softened

Cook the onions slowly in the butter for about 10 minutes until very tender but not browned. Place in a mixing bowl. Add the beef, butter, seasonings and egg to the onions in the mixing bowl and mix thoroughly to combine ingredients. Form into patties ¾-inch thick. Cover with waxed paper and refrigerate until ready to use.

Just before sautéing, roll the patties lightly in the flour. Shake off excess flour. Place butter and oil in a skillet and set over moderately high heat. When you see the butter foam begin to subside, sauté the patties for 2 to 3 minutes or more each side, to desired doneness. Remove patties from skillet to warm plate.

Pour the fat out of the skillet. Add the liquid and boil it down rapidly, scraping up the coagulated pan juices, until it had reduced almost to a syrup. Off heat, swirl butter by half-tablespoons into the sauce until it is absorbed. Pour the sauce over the hamburgers and serve. Makes 6 burgers.