Whisk eggs, cottage cheese, dry mustard, chili powder and pepper in medium bowl. Stir in green onion, celery and red pepper. Set aside.
Spray four 1/2 cup ramekins (125 mL) with cooking spray. Place one tortilla in each ramekin, pressing to fit. Pour equal amount of egg mixture into each tortilla cup.
Bake in preheated 375°F (190°C) oven until set, 20 to 25 minutes. Let stand for 5 minutes and serve.