Instructions

• Using a mortar and pestle, mash garlic, chile, sugar, teaspoon of the salt and garlic together until a fragrant, slightly sticky paste forms, 1 minute. Transfer mixture to a small bowl; stir in vinegar and fish sauce.
• Rinse onion slices in a fine mesh strainer under cold water, about 10 seconds. Shake to drain well; stir onion into vinegar mixture.
• Add peanuts to mortar; pound using pestle until coarsely crushed. Set aside.
• Cut mushrooms in half lengthwise, and slice diagonally into 2-inch-long, ¼-inch-thick pieces (about 3 cups sliced). Heat oil in a 10-inch nonstick skillet over medium until oil ripples. Add mushrooms and remaining ¼ teaspoon salt; cook, stirring occasionally, until softened, about 3 minutes. Remove from heat. Transfer mushrooms to a large bowl; let cool completely.
• Add cabbage, carrot, mint and crushed peanuts to mushrooms. Pour onion-dressing mixture over cabbage; toss until combined and cabbage softens slightly, about 1 minute. Transfer to a large platter. Sprinkle with fried onions; serve immediately.