Cook the asparagus in large skillet of boiling salted water until almost crisp-tender, about 5 minutes. Drain the asparagus. Transfer to a bowl of ice water and cool. Drain and pat dry. (Can be prepared 1 day ahead; cover and chill).
Melt the butter with sesame oil in a heavy, large skillet over medium-high heat. Add the asparagus and saute until crisp-tender, about 2 minutes. Mix in the lemon juice and soy sauce and toss to coat. Season to taste with salt and pepper.
Transfer to a platter. Sprinkle with sesame seeds and serve.
Notes
If you are preparing this recipe as gluten free, just be sure to use a brand of soy sauce that is know to be GF.