In a small bowl, whisk together the oyster sauce, sesame oil, vinegar, maple syrup, sesame seeds, chili flakes and garlic. Set aside.
Add 1 tbsp of neutral oil to a large skillet and set over medium-high heat. Once shimmering, add the asparagus and a generous pinch of salt. Cook the asparagus, tossing occasionally, until the spears are bright green and beginning to soften, about 2-3 minutes.
Pour over the sauce and toss to coat the asparagus. Continue to cook, tossing constantly, until the sauce thickens, becomes sticky and clings to the asparagus, another 2-3 minutes. Remove from the heat and serve immediately.