Pork w/ Orange Sauce

1 pork tenderloin ( 1 1/4 lbs.)
1 lg. navel orange
1 tsp. olive oil
1 sm. red onion (sliced)
1 tbl. dijon mustard
salt & pepper

Cut pork into four slices, press each slice with the palm of your hand to flatten a bit. Season both sides with 1/4 tea. salt and 1/4 tea. pepper. From orange, grate 1/2 tea. peel and squeeze 1/2 c. orange juice.

Heat skillet on med. high heat and add oil, then pork in a single layer. Sprinkle onion in the pan and cook 4 minutes until pork browns. Turn pork over and stir onion, cook 5 mins. longer. Transfer pork to plate while leaving onion in skillet.

Add mustard, orange peel, and juice in skillet and cook for 1 min. stirring occasionally.

Serve pork over brown rice and spoon sauce over the top.