Cabbage Schnitzel

Name: Cabbage Schnitzel
Ingredients: 6 tbsp. vegetable oil, divided; 8 oz. cremini mushrooms, thinly sliced; 1 tsp. (or more) kosher salt, divided; 1/2 yellow onion, finely chopped; 1/4 c. all-purpose flour; 1/4 c. dry white wine; 2 c. low-sodium vegetable broth; 1 sprig thyme; 1 tsp. vegetarian Worcestershire sauce; 1/2 tsp. freshly ground black pepper; 1 head green cabbage; 2 1/2 tsp. kosher salt, plus more; 1 c. (120 g.) all-purpose flour; 5 large eggs, lightly beaten; 2 1/2 tsp. Dijon mustard; 2 1/2 c. panko bread crumbs; 1 tsp. freshly ground black pepper; Neutral oil, for frying (1 1/2 to 2 c.); 1/4 c. fresh parsley, finely chopped