While the grill is heating up, trim the bottom 2 inches off the asparagus with a knife—this part is tough. You can save the ends to make vegetable stock.
Place the asparagus on a sheet pan. Drizzle with oil and season with kosher salt to taste.
Using tongs, place the asparagus on the grill perpendicular to the grates so they don’t fall through. This works best with thick spears.
Cook for 7–9 minutes until charred and the spears have softened. Rotate the asparagus to ensure even cooking. If it's charring but still too hard, move it to a cooler part of the grill.
Remove the asparagus when done and transfer it back to the sheet pan. Serve immediately.