In a medium bowl, whisk together mustard, vinegar, stevia and 2 Tbsp beef broth. Set aside
Place sirloin strips in non stick saute pan and season with salt and pepper. Add remaining beef broth to pan and cook over medium heat until steak is desired doneness (about 5 minutes on each side). Let cool 5 minutes the slice into strips.
Place onions in the same pan as the steak (no need to wash!) and cook, tossing in the pan juice for one minute just to heat.
Toss steak back into saute pan and add dijon dressing. Toss well then divide between two plates. Top with parsley. Serve warm
– For AP version, serve over a bed of arugula – Vegetable broth will also work well – Chicken Breast will work well in place of steak