Pour 1 inch of water into a saucepan. Fit a steamer basket into the saucepan. Bring the water to a boil.
Chop off about an inch from the bottom of the asparagus. There's generally no need to peel them since we're using medium-thickness spears, but if some of the spears are very thick or woody, go ahead and peel the bottom.
Once the water has boiled, place the asparagus in the steamer basket. Cover and steam until the asparagus are just barely tender, about 5 minutes. Thinner spears will require just 3 minutes of steaming.
Immediately remove the asparagus from the steamer and transfer to a serving platter. Drizzle it with melted butter and lemon juice, and sprinkle with kosher salt, black pepper, and garlic powder. Serve immediately.
It's important to avoid overcooking asparagus. If it's ready before you are ready to serve it (perhaps the main dish is still cooking), you should still remove it to a serving plate. Cover it with foil to keep it warm. It's better to serve it crisp at room temperature than to overcook it in an attempt to keep it warm.