1. Preheat oven to 425° F. Carefully unroll puff pastry onto lightly floured piece of parchment paper. Roll out with floured rolling pin to a 9 x 12 rectangle. Poke the pastry all over with a fork. 
2. Whisk together the ricotta, 1/2 cup Parmigiano-Reggiano, egg, 1/2 teaspoon salt, lemon zest and lemon juice. Spread cheese mixture evenly over the top of pastry, leaving a 1-inch border on each edge.
3. Toss asparagus with olive oil, remaining salt and a generous sprinkling of black pepper. Layer asparagus evenly over ricotta. Brush exposed crust with oil. Bake for 35 minutes, or until asparagus is tender and crust is golden-brown. Sprinkle with remaining Parmigiano-Reggiano. Garnish as desired.

Calories: 256, Fat: 18 g (6 g Saturated Fat), Cholesterol: 40 mg, Sodium: 337 mg, Carbohydrates: 15 g, Fiber: 2 g, Protein: 8 g.