Boil egg noodles as directed on package to desired doneness.
While noodles are cooking, slice sirloin into 1" thin strips. Heat 1 tbsp oil in large skillet, and add sirloin. Stir and cook for 5 minutes.
Remove sirloin from pan, and add remaining 1 tbsp oil to pan. Saute onions and mushrooms until tender and onions are caramelized, abt 3 minutes. Add sirloin, teriyaki or Worcestershire sauce, thyme, salt and pepper. Cook an additional 3 minutes.
Mix flour in cold water and add to pan. Stir continuously until thickened. Remove from heat and add sour cream.
Drain noodles and lightly drizzle with olive oil. Serve stroganoff over noodles.