1In a non reactive pot heat vegetable oil over med-high heat. Add the white mushrooms, baby portabella, onion and garlic and cook, stirring until the mushrooms release thier liquid, about 5 minutes.
2Add wine, soy sauce, bay leaf, rosemary sprig, thyme dried mushrooms, and 6 cups of water. Bring to a boil, cover, reduce heat and simmer for about 1 hour.
3Pour the broth though a fine strainer into a heat proof bowl. Repeat and leave any paritcles at the bottom of bowl.
Broth can be refrigerated for up to 4 days.
Freeze in 2 cup size portions for 1 month.