Cut up the onion, mushrooms, and garlic (if not using pre-minced).
Heat olive oil in a large skillet over medium heat for one minute. Add the onion and mushrooms and saute over medium heat for eight minutes, stirring occasionally, or until the mushrooms are browned and onion is beginning to soften.
Stir in the beef and garlic. Continue to cook over medium heat for another four minutes, stirring occasionally, or until the beef is just cooked through.
Stir in the coleslaw and seasonings. Continue to cook for another five minutes, stirring often, until the cabbage is crisp-tender.
Stir in the giardiniera and broth. Heat for another few minutes, then serve.
Notes
I highly recommend mild giardiniera — I used hot from ALDI, and this dish turned out extremely spicy. Even though I quite like spice, I’d switch to the mild next time myself. If you’re very sensitive to spice, you might even start with less giardiniera, adding it in to taste.