Combine flour and salt. Combine oil and water; stir well. Add oil mixture to dry ingredients, stirring with a fork just until dry ingredients are moistened. Shape into a ball; chill 30 minutes.
Roll dough to 1/8-inch thickness between 2 sheets of heavy-duty plastic wrap. Place in freezer 5 minutes. Remove bottom sheet of plastic wrap. Fit dough into a 10-inch quiche dish; remove top sheet of plastic wrap. Fold edges under and flute, if desired. Prick bottom of pastry shell lightly with a fork. Bake at 400° for 15 minutes or until golden.
Coat a nonstick skillet with cooking spray; place over medium-high heat until hot. Add mushrooms, onion, and garlic; saute until tender. Combine cottage cheese and next 5 ingredients; stir in spinach and mushroom mixture. Spoon mixture into prepared pastry shell. Bake at 350° for 35 minutes. Remove from oven, and sprinkle with Swiss cheese. Bake 5 minutes or until cheese melts. Let stand 10 minutes before slicing.