SAUCE- Heat oil in a pan. Saute onion and garlic till translucent. Add crushed tomatoes, salt and seasonings. Cover and cook for at least 20 minutes over low flame.
Preheat oven to 375 C.
Cook and drain whole wheat lasagne noodles as per package instructions.
Blanch spinach leaves in boiling water for 30 seconds. Drain and immediately transfer in ice cold water. Drain and squeeze thoroughly. Chop roughly.
Mix ricotta cheese, 3/4 cup mozzarella cheese, parmesan cheese, blanched spinach leaves and seasonings.
Pour 1 cup sauce into 8*2" baking dish.
Spread 1/2 cup cheese spinach mixture over each lasagne noodle sheet. Roll up and place over sauce, seam side down.
Top the rolls with remaining sauce and remaining mozzarella cheese.
Bake covered 20 minutes. Uncover; bake until heated through, 5-10 minutes.