Heat a large skillet over medium heat and add the Italian sausage and lean ground beef. Cook for about 5-8 minutes until browned. Stir in diced shallots and onion soup mix until shallots are translucent.

Prepare the vegetables by slicing large white mushrooms and poking holes in them. Cut the carrots into playful pumpkin shapes or regular sizes. Chop the celery.

Transfer browned meat to the slow cooker. Add prepared vegetables, the second packet of onion soup mix, beef broth, diced tomatoes, and red wine vinegar. Stir to combine.

Cover the slow cooker and set to cook on high for 2-3 hours or low for 4-6 hours. Monitor during the last hour for tenderness.

Once cooked, ladle the stew into bowls and serve hot, optionally garnished with fresh parsley.