MEDALLIONS OF VEAL WITH BLACK CAVIAR

1 stick (1/2 cup) unsalted butter
1 medium onion, sliced thick
1/2 tsp. freshly ground pepper
2 oz. white wine vinegar
6 oz. dry white wine
2 cups veal or chicken stock
1 1/2 cups heavy cream
1 loin of veal, well trimmed and cut into 10 (3 oz each) medallions
1/4 cup sour cream, room temperature
4 oz russian sturgeon caviar
1/2 bunch chopped cilantrillo

Heat 1/3 of the butter in a stainless steel or enameled skillet, add onion, and saute over low heat for 2 minutes.

Add the pepper and vinegar, increase heat to moderate and reduce slightly.

Add wine, reduce by half, add stock and reduce to syrup.

Add cream and reduce till just thickened. Strain sauce through a fine sieve and keep hot.

In another skillet, heat remaining butter, add veal medallions, and saute over moderate heat for 4-5 minutes on each side.

Transfer 2 medallions to each of 4 hot serving plates, pour equal amounts of sauce over each medallion, and grind on a little pepper to taste.

To serve, top each medallion first with a teaspoon of sour cream, then with 1/2 ounce of caviar. Sprinkle tops with chopped parsley and serve immediately.