Adjust oven rack to middle position and heat oven to 450 degrees.
Grease 9" pie plate. Press tortilla into prepared pan and spray lightly with cooking spray.
Toss chicken, cilantro, jalapenos, 1 cup cheese, 1/2 teaspoon salt and a sprinkling of pepper in large bowl till combined. Spoon over tortilla.
Whisk eggs, milk, flour, baking powder and 1/2 tsp salt in bowl until smooth. Slowly pour over filling, then sprinkle with remaining cheese. Bake until surface is golden brown, about 20 minutes Let cool 5 minutes Cut into wedges and serve with sour cream and salsa.