How to Make It
Heat butter and oil in a large skillet over high until butter foams vigorously. Add morels; cook, stirring often, until beginning to brown, about 4 minutes. Add salt; cook, stirring often, until mushrooms are just wilted, about 4 minutes. Stir in XO sauce; cook, stirring often, 2 minutes. Stir in mushrooms, scallions, vinegar, and pepper.