Trim the woody ends off the asparagus and rinse the spears under cold water. Pat dry thoroughly with a clean towel.
Preheat your large skillet over medium-high heat until hot, creating a gentle sizzle when you add the garlic butter.
Add the garlic butter to the skillet, allowing it to melt and bubble, releasing fragrant aromas of garlic and butter within about 30 seconds.
Place the asparagus in a single layer in the skillet, laying the spears flat so they make good contact with the hot surface.
Sauté the asparagus for 3-4 minutes, shaking the pan occasionally, until they turn bright green and start to blister in spots, with some tips curling.
Watch the garlic carefully; it should be golden and fragrant. If it starts to darken too quickly, lower the heat slightly to prevent bitterness.
Continue sautéing for another 2-3 minutes until the asparagus is tender but still crisp, with a slight jiggle when shaken.
Remove the skillet from heat, then season with salt to taste and add a splash of lemon juice, if using, to brighten the flavors.
Toss gently to coat the asparagus evenly with garlic butter and seasonings, then transfer to a serving plate.
Let rest for a minute to allow flavors to meld, then serve immediately while the asparagus is hot, fragrant, and perfectly crisp-tender.