Cut tenderloin crosswise into 12 equal rounds. Pound beef rounds to flatten to generous 1/4-inch-thick medallions. Season lightly with salt and pepper.
Melt 2 tablespoons butter in heavy large skillet over medium-high heat. Working in batches, saute beef in skillet until brown on outside but still pink in center, about 2 minutes per side. Transfer beef to plate.
Add remaining butter to same skillet. Add garlic, shallots and thyme; sauté until tender, about 3 minutes. Add flour; stir 1 minute. Add broth and wine. Boil until sauce thickens and is reduced to 1 1/4 cups, stirring occasionally, about 12 minutes.
Return beef and any collected juices to sauce in skillet; heat through, about 1 minute. Transfer beef to plates and spoon sauce over beef.