Preheat oven to 350F. Spray a 9-inch pie pan with cooking oil, set aside.
Cook spaghetti according to package directions (without adding salt) , drain.
In a medium bowl lightly beat two egg whites, Parmesan cheese, cottage cheese, olive oil and cooked spaghetti. Toss to thoroughly coat. Press spaghetti mixture into bottom and up sides of the prepared pie pan to create the crust.
In a small bowl combine 2 egg whites and cottage cheese, spoon on top spaghetti in pie pan.
Line a large skillet with a few teaspoon of water, add fennel and cook until fennel begins to soften (about 2-3 min.) add turkey, garlic, Italian seasoning, pepper, fennel seeds, red pepper flakes and continue cooking until turkey is fully cooked and fennel is soft. Drain off any fat. Stir in tomato sauce and spinach and continue to cook until spinach begins to wilt. Spoon over cottage cheese mixture in pie pan.
Bake 20 min. (uncovered) until heated through. Sprinkle mozzarella over top of pie and cook an additional 5 min. until cheese is melted and bubbling. Remove from oven and let stand 15 min. before serving. Garnish with chopped spinach or fennel fronds if desired.