Bring a large pot of salted water to a boil. Add the elbow macaroni and cook according to the package instructions until al dente, usually about 7-8 minutes. Drain well and set aside.
Heat olive oil in a large skillet over medium-high heat. Add the ground beef and cook, breaking it apart with a spoon, until fully browned and no longer pink, about 6-8 minutes. Drain any excess fat.
To the browned beef, sprinkle garlic powder, onion powder, salt, and pepper. Stir well to combine. Pour in the can of chili with no beans, mixing thoroughly. Simmer for 3-4 minutes to let the flavors meld.
In a large bowl or directly in the baking dish, combine the cooked macaroni with the chili and beef mixture. Mix well to ensure every noodle is coated with the chili goodness.
Fold in half of the cheddar and mozzarella cheeses along with the chopped green onions into the pasta mixture. This makes sure the cheese is evenly distributed throughout the bake.
Transfer the macaroni mixture into your prepared baking dish. Sprinkle the remaining cheddar and mozzarella cheese evenly over the top. If you’re using turkey bacon, sprinkle the cooked and crumbled pieces over the cheese for a crispy finish.
Preheat your oven to 350°F (175°C). Bake the pasta for 20-25 minutes, or until the cheese is melted, bubbly, and starting to turn golden brown.
Remove the pasta bake from the oven and let it sit for 5 minutes to set. Garnish with a few extra chopped green onions if you like, then scoop out generous portions and serve warm.