Preheat the oven to 200°C (approximtely 400°F) convection.
Trim bottom 1/3 of the asparagus, peel and cook the stalks in boiling salted water with sugar until al dente, about 10 minutes. Rinse scallions, trim and cut into rings. Peel the garlic, chop finely and sauté in an oven-proof pan in butter, 1-2 minutes. Beat the eggs with the cream fraiche and season with salt, pepper and nutmeg. Pour over the scallions. Top with the asparagus spears. Sprinkle with cheese and bake until golden brown, 10-15 minutes.