Heat water in a large pot, add salt and 1 tbsp. oil. Bring to a boil. When water comes to a boil add in the uncooked pasta.
Cook pasta until well cooked and tender; then drain.
Heat 2 tbsp. oil in a large skillet; add chicken cubes and fry for a couple minutes.
Stir in 1 can of the tomato sauce. Stir for a minute or so. Add in the other 2 cans of tomato sauce and sour cream. Stir until well heated. Remove from heat.
Preheat oven to 350 degree F (175 degree C.) In a greased 9 x 13 inch baking pan layer the cooked and drained pasta, then the cottage cheese and cream cheese. Pour the tomato sauce mixture over the top and sprinkle with the green bell pepper and green onion.
Place pan in oven and bake for 35 to 40 minutes. Remove from oven and let stand for 10 to 15 minutes before serving.