Preheat oven to 450°.
Heat oil in a nonstick skillet over medium-high heat. Add leek and asparagus; sauté 5 minutes or until lightly browned. Stir in sage, salt, and pepper.
Arrange spinach over crust; leave a 1-inch border. Top with leek mixture; sprinkle with cheese. Place on a baking sheet. Bake at 450° for 10 minutes.