Melt the butter in a skillet on thestovetop over medium/high heat. Add the onions and garlic to the skillet and saute until slightly softened.
2 tablespoons unsalted butter, 1 cup diced yellow onion, 1 tablespoon minced garlic
Add the ground beef and cook until no longer pink, breaking the meat up with a spatula as it cooks.
1 pound ground beef
Add the prepared beef/onion mixture to the pot of a slow cooker, along with the celery, potatoes, tomatoes, tomato paste, salt, pepper, and Italian seasoning.
1 cup chopped celery, 4 cups cubed Yukon gold potatoes, 1 6- ounce can tomato paste, ½ teaspoon salt, ¼ teaspoon ground black pepper, 1 teaspoon Italian seasoning
Pour the vegetable broth and crushed tomatoes over the top of everything and stir to fully combine.
4 cups vegetable broth, 1 cup canned crushed tomatoes
Place the lid on the slow cooker and cook on HIGH for about 3 hours, or until the potatoes are fork-tender. Add the frozen vegetables to the slow cooker and cook for an additional 30 minutes.
1 12- ounce bag frozen mixed vegetables
Serve warm with a side of bread or biscuits.