Snap the woody ends off the asparagus base. It will naturally break at the right point. Cut them into 1-inch pieces.
Slice mushrooms into ½-inch thick slices.
In a medium skillet over medium-high heat, melt 1 tablespoon of butter. Once hot, add the cut asparagus. Cook, stirring occasionally, for 3 to 4 minutes, or until the asparagus is cooked but still crisp. Transfer to a plate.
Add another tablespoon of butter and let melt. Add sliced mushrooms and toss with the butter mixture. Cook for about 3 to 4 minutes, stirring occasionally.
Reduce heat to medium, add all remaining ingredients, cook for 2 to 3 minutes, stirring frequently, until mushrooms are cooked and garlic is fragrant.
Add the cooked asparagus, 2 tablespoons water and the remaining tablespoon of butter. Stir for 10 to 20 seconds and remove from heat.
Video
Notes
Don't stir too much - Limit stirring while cooking to allow for browning and caramelization. Stir only occasionally.Don't slice the mushrooms thin - Slicing them about ½ an inch thick ensures they cook quickly while retaining their texture, instead of shrinking away.