Pork Tenderloin without pecans

Pastry: 3 c. unbleached flour 1 1/2 tsp. salt 3/4 c. iced water 4 1/2 tsp. vinegar 2 sm. egg yolks 1 c. butter or vegetable shortening (DO NOT USE MARGARINE)[...]

6 Large Brown or White Mushrooms 1/4 Cup Red Onion, minced 2 Cloves Garlic , pressed/minced 2 Tbs Parsley , chopped 1 tsp Herbs de Provence 1/4 Cup Red Wine 1[...]

1 pork tenderloin (cut into 3/4-inch medallions) 2 -3 tablespoons oil (any vegetable oil is fine) 1 medium onion , finely chopped 2 cups sliced fresh[...]