Pierogi Casserole

12 lasagna noodles
1/3 cup vegetable oil
4 to 5 medium-sized onions, finely chopped
1/2 teaspoon black pepper
1-1/2 cups (6 ounces) dry cottage cheese
6 cups warm seasoned mashed potatoes (instant potatoes are fine)

Preheat the oven to 350 degrees F. Cook the noodles according to the package directions and drain; set aside. Meanwhile, in a large skillet, heat the oil over medium-high heat. Saute the onions for 8 to 10 minutes or until golden brown. Reserve 1/2 cup onions for topping. Add the remaining onions, pepper, and cheese to the potatoesand mix well. Place 3 noodles on the bottom of a 9 x 13-inch glass baking dish that has been coated with nonstick vegetable spray.Spread the noodles with one-third of the potato mixture. Layer with 3 more noodles and continue until there is a total of 4 layers of noodles and 3 layers of potatoes (with a noodle layer on the top). Spread the reserved onions on top. Cover with aluminum foil and bake for 30 minutes or until heated through.