Weight Watchers Salisbury Steak Meatballs Recipe

2 tsp olive oil, divided

1/2 cup minced onions

1/2 lb 93% lean ground beef

1/2 lb 93% lean ground turkey

1/3 cup whole wheat seasoned breadcrumbs

1 large egg, beaten

2 tablespoons tomato paste, divided

kosher salt

pinch black pepper

1 tbsp all-purpose flour

1 tsp red wine vinegar

2 tsp Worcestershire sauce, to taste

1/4 tsp mustard powder

5 oz sliced mushrooms

1 1/4 cup reduced sodium beef broth

chopped parsley for garnish (optional)