Preheat oven to 400°F.

In a skillet, cook the ground beef and onion over medium heat until browned. Drain excess grease.

Stir in vegetables, tomato paste, Worcestershire, garlic powder, thyme, salt, and pepper. Cook 2-3 minutes until combined and heated through.

Transfer the beef mixture to a small baking dish.

Spread the prepared Idahoan mashed potatoes evenly over the top.

Sprinkle with shredded cheddar cheese if using.

Bake 15-20 minutes, until the top is golden and the edges are bubbling. Let cool slightly before serving.