Preheat oven to 350°F and grease a 9x9 or 9x13-inch baking dish with nonstick spray. Set aside.

In a skillet over medium heat, cook ground beef, seasoning with salt and pepper, and breaking it into crumbles. Transfer to a large bowl once browned.

Add tomato purée, corn, and green beans to the cooked meat. Stir well to combine and set aside.

In a separate bowl, mix potato flakes with boiling water, sour cream, and butter until smooth. Season with salt and pepper.

Spread the meat and vegetable mixture into the bottom of the prepared baking dish.

Top the meat layer with the mashed potato mixture, spreading it into an even layer.

Cover the dish with foil and bake for 30 minutes, until bubbling around the edges.

Uncover, sprinkle cheese on top, and bake for another 10 minutes until the cheese is melted.

Serve warm and enjoy!