This is a really great lasagna, though I only use about 1/4 the asparagus:
Alpine Asparagus Lasagna
from Colorado College Cookbook
4 lbs fresh asparagus
2 T olive oil
1/4 C butter
1/4 C flour
1/2 C water
1 1/2 C vegetable broth
2 C shredded moxarella
1 T finely grated lemon zest
16 oz lasagna noodles cooked al dente and drained
1 2/3 C freshly grated Parmesan chese, divided
1 C whipping cream
Preheat oven to 500 degrees. Cut and discard 1 in. from bottom of asparagus stalks. Toss stalks with olive oil. Arrange in single layer, on 15 x 10 inch baking sheet. Roast 5 - 10 minutes until crisp tender. Remove from oven, sprinkle with salt to taste, and set aside to cool.
Reduce oven temperature to 400 degrees. Cut roasted asparagus into 1/2 inch pieces and set aside. In large saucepan, melt butter over medium heat. Add flour and cook, stirring constantly, 3 minutes. Combine water and vegetable broth and add, in slow, steady stream, whisking constantly. Cook 5 minutes. Add mozarella and lemon zest and stir until smooth.
Butter 13x9x2 inch baking pan. Place single layer of lasagna noodles in prepared pan. Pour half of the sauce mixture over noodles. Layer half of the reserved asparagus over sauce. Sprinkle with 1/2 C of the Parmesan. Top wih second layer of noodles, remaining sauce, remaining asparagus, 1/2 C of the Parmesan and another layer of noodles.
In small bowl, combine cream and a pinch salt. Whip to soft peaks and spoon evenly over noodles. Sprinkle remining 2/3 C Parmesan on top. Bake 30 minutes, or until golden brown and bubbling. Let stand 20 minutes.