Heat a large skillet over medium-high heat. Add the ground beef, onion, and garlic. Cook and stir until the beef is browned and the onion is tender, about 5-7 minutes. Drain any excess fat.
Once the beef is browned, add the frozen mixed vegetables, beef broth, Worcestershire sauce, salt, and pepper to the skillet. Stir well to combine and bring to a simmer, allowing the flavors to meld.
In a medium-sized mixing bowl, whisk together the flour, baking powder, baking soda, and garlic powder. Add in the cold butter and use a pastry cutter or your fingers to incorporate until the mixture resembles coarse crumbs. Stir in the cheddar cheese and then pour in the buttermilk, mixing just until combined.
Preheat your oven to 375°F (190°C). Transfer the beef mixture to an oven-safe baking dish. Drop spoonfuls of the biscuit mixture over the top, leaving some gaps.
Bake for about 25-30 minutes, or until the biscuits are golden brown and cooked through. Remove from oven and garnish with chopped parsley before serving.
Notes
Store leftovers in an airtight container in the refrigerator for up to 3 days. You can also freeze the dish for up to 2 months.