Cook noodles according to package directions, omitting salt and fat; drain.
While noodles cook, heat a large nonstick skillet over medium-high heat. Coat pan with cooking spray. Add steak; sauté 5 minutes, browning on all sides. Remove from pan; cover.
Melt butter in pan over medium-high heat. Add shallots and mushrooms; sauté 4 minutes. Add garlic; sauté 30 seconds. Stir in soy sauce. Sprinkle flour over mushroom mixture; cook 1 minute, stirring constantly. Gradually add broth, stirring constantly. Add pepper, salt, and thyme sprigs. Bring to a boil; cook 2 minutes or until thickened. Return beef to pan; cook 1 minute or until thoroughly heated. Discard thyme sprigs. Garnish with thyme leaves, if desired.
Briefly cooking the gravy with thyme sprigs saves the time of stripping the tiny leaves from the stem, but still gives you the herb's woodsy flavor.
Used worcestershire sauce instead of soy as suggested by other reviewers and thickened the sauce with cornstarch at the very end, adding more beef broth to thin the gravy. Was very flavorful, but would use rice or potatoes next time to absorb more flavor than egg noodles.
I like the overall flavor but had to make some adjustments. Salt and pepper meat before browning, substitute Worcestershire for the soy sauce, ground black and green peppercorn, deglaze with 1/2 cup of red wine reduce by half before adding flour and 11/4 cup broth.
Served over white rice to pick up all the yummy sauce. I cooked the meat a bit too long so need to simmered down the sauce and keep it under 5 mins when returning the meat to the pan next time.
I altered this recipe a bit by only doing 2 things differently. I took everyone's advice and added 1 tbsp of Worcestershire. I'm very happy I did. The biggest change was not thickening the broth until after everything had simmered for about an hour. I wanted to make sure the beef was tender (I did use top sirloin) so I omitted the step that adds the flour after sauteing the mushrooms. I let everything simmer in a covered skillet for about an hour. Then I mixed approximately 2 tbsp flour with some of the reduced broth in the pan and then stirred it back into the pan and let it thicken for a few minutes. OH MY GOSH! This was an amazing dish that I will continue to serve over and over again! Ok, maybe it's not quick, but it's really, really good! I didn't give this 5 stars because I altered it. My altered version is worth at least 10 stars!