Bring a large pot of salted water to a boil. Add the macaroni and cook for about 7 minutes, until just al dente. Scoop out ¼ cup of the pasta water, then drain the macaroni and set both aside.

While the pasta cooks, brown the ground beef in a large, deep skillet or saucepan over medium-high heat, breaking it up with a spoon, for 6 to 8 minutes, until no pink remains. Drain off the fat.

Reduce the heat to low. Stir in the garlic powder, chili powder, salt and pepper, mix well, and cook for about 5 minutes, stirring occasionally, so the spices bloom in the meat.

Add the cooked macaroni and the undiluted tomato soup and stir until everything is coated. Cook over medium-low heat for 3 to 5 minutes, stirring often, until heated through. If it seems too thick, stir in a splash of water or the reserved pasta water.

Just before serving, sprinkle the shredded cheese over the top. Cover and heat for 1 to 2 minutes, until the cheese melts. Garnish with chopped fresh parsley if you like, and serve hot.