1 (2 lb.) flank steak
2 cloves garlic, minced
2 Tbsp. vegetable oil
1 Tbsp. white wine vinegar
1 tsp. salt, divided
1/2 tsp. white pepper
1/2 c. white wine or broth
2 Tbsp. each chopped shallot and fresh tarragon, divided
2 Tbsp. chopped fresh chervil, divided
1 bay leaf
4 egg yolks
1 1/2 tsp. water
8 Tbsp. (1 stick) butter

Score both sides of steak in a diamond pattern. Rub with garlic. Place in a shallow bowl. Coat lightly with the vegetable oil, vinegar, 3/4 teaspoon salt and 1/4 teaspoon white pepper. Let steak stand for 30 minutes.

Preheat the grill to medium. Grill steak 4-inches from the heat for 4 to 5 minutes per side.

Combine the wine, shallot, half the tarragon, half the chervil, bay leaf and remaining salt in a medium skillet. Bring to a boil, reduce heat and simmer, stirring occasionally, until the mixture is reduced by two-thirds.

Place egg yolks and water in the top of a double boiler. Pour over boiling water. Cook, beating continually, until the egg yolks begin to thicken, about 3 minutes. Stir in butter, 1 tablespoon at a time. Remove from heat. Stir in the wine mixture and the remaining tarragon, chervil and white pepper. Discard bay leaf. Serve sauce with thinly sliced steak.