A smooth, rich dish dotted with tender morsels of asparagus: Pair it with a green salad and serve for lunch, or offer it as a vegetable side dish.
Wash and trim asparagus. Cut into 1-inch lengths. Cook in boiling, salted water until tender, 3–4 minutes. Drain asparagus and submerge in ice water to stop cooking. Set aside.
Preheat oven to 350°. Melt butter in a large saucepan over medium heat. Add onion and cook, stirring occasionally, until tender, 6–8 minutes. Sprinkle flour on mixture and cook until it foams.
Gradually stir in cream and continue cooking until thickened.
Remove from heat and stir in cheese, salt, pepper, and lemon juice. Blend in beaten eggs.
Generously butter a round casserole or soufflé dish.
Gently blend asparagus into cheese mixture and pour into prepared dish. Sprinkle surface with nutmeg and bake 30–40 minutes or until the blade of a knife inserted in the center comes out clean.