Cheesy Beef Stroganoff Pasta

Name: Cheesy Beef Stroganoff Pasta
Prep time: 10 min
Cook time: 45 min
Total time: 55 min
Cuisine: American
Ingredients: 1 lb lean ground beef; 1/2 cup diced onion; 1 1/4 tsp kosher salt, divided; 1 tsp minced garlic (about 2 cloves); 8 oz cremini mushrooms, chopped; 1 tbsp all-purpose flour; 2 cups low-sodium beef stock, warmed; 1 tbsp + 1 tsp worcestershire sauce; 2 1/2 tsp dijon mustard; 7 oz plain greek yogurt; 3/4 lb rigatoni; 1 1/2 cups shredded mozzarella cheese