Preheat oven to 350 degrees Fahrenheit (175 degrees Celsius)
In a large pasta pot, cook the pasta 2 minutes short of the package directions. Reserve ¾ cup of the pasta cooking water and drain the pasta.
Place the hot pasta back into the cooking pot and add the cream cheese and the reserved cooking water. Stir well until the cream cheese is completely melted and the spaghetti is well coated.
Add the creamy pasta in an even layer in a 3-quart casserole dish that has been sprayed with cooking spray.
Meanwhile, in a large skillet, brown the ground beef and onion over medium/high heat. Stir in the garlic, chili powder, paprika, cumin, coriander, salt, and pepper.
Cook and stir an additional 2-3 minutes.
Reduce the heat to medium/low.
Add the drained beans and salsa to the ground beef mixture and stir well to combine.
Top the creamy spaghetti with the ground beef chili mixture in the 3-quart casserole dish.
If baking immediately, bake for 20 minutes in a 350-degree oven.
Top with cheese and return to the oven until the cheese is melted.