Meanwhile, in 4-quart Dutch oven, melt butter over medium heat. Add onion and salt; cook 4 to 6 minutes, stirring frequently, until onions begin to brown and soften. Add mushrooms, thyme and sage. Cook 6 to 8 minutes, stirring occasionally, until mushrooms release juices and then brown. Add wine; simmer 3 to 5 minutes, scraping pan to release browned bits. Once liquid is almost evaporated, remove from heat.