1 medium headescarole, cleaned, dried, and torn into bite-size pieces
1/4 cupolive oil
1 poundmushrooms (such as shiitake, button, or cremini), cleaned, stems removed, and quartered
2 medium garlic cloves, finely chopped
1 large shallot, thinly sliced
1 teaspoon fresh thyme leaves, minced
Freshly ground black pepper
5 tablespoonsred wine vinegar
Place the escarole in a large, nonreactive bowl and set aside. Heat the oil in a large frying pan over high heat. When the oil smokes, add the mushrooms, garlic, shallot, and thyme and season generously with salt and pepper. Cook, stirring occasionally, until the mushrooms are browned and tender, about 5 to 6 minutes.
Remove the pan from heat and transfer the mushrooms to the bowl with the escarole. Pour the vinegar into the pan. Stir, scraping up any browned bits from the bottom of the pan, then pour over the salad. Toss all the ingredients together, season with additional salt and pepper, and serve.