Squash au Vin

Recipe found on bonappetit.com Makes 4–6 servings   Ingredients: 5 Tbsp. extra-virgin olive oil, divided 4 oz. crimini mushrooms, quartered Kosher salt 1 large onion, thinly sliced 4 large shallots, halved through root ends, peeled 6 garlic cloves, 5 thinly...