Heat oven to 400 degree's.
Cook noodles according to package instructions for al dente (ensure you salt the water like the sea).
To a medium skillet on medium heat, melt butter until bubbling.
Add flour one tbsp at a time whisking to dissolve in butter.
Allow butter and flour to cook for about a minute to remove the raw flour flavor.
Turn the heat down to medium-low and slowly pour in the milk while whisking simultaneously. If you don't whisk while you pour you'll have huge lumps of flour in your sauce and you don't want that. Whisk, whisk, whisk!
Once you add the milk to the skillet and it's well mixed with the roux, add in the heavy cream slowly while whisking.
Bring the milk to a low simmer while whisking, ensuring you're getting all corners of the sauce.
As the sauce simmers it will begin to thicken, after about 5 minutes.
Once the sauce begins to thicken, turn the heat to low and season with nutmeg, garlic powder, onion powder, all-purpose seasoning, and paprika.
Whisk the seasoning until well incorporated.
Use a spoon to dip in the sauce and draw a line with your finger on the back of the spoon. If the line stays the sauce is thick enough to add the cheese and you can turn off the heat. If the line does not stay, continue to simmer for another minute or two until thicker.
Turn off the heat and add cheese one handful at a time while whisking to dissolve the cheese into the sauce.
After you've added two cups of cheese (or more to your desired preference) combine with the noodles and mix to incorporate.
It might look like you have too much sauce for the noodles but remember that the noodles will absorb the sauce as it sits.
Allow the sauce and the noodles to become friends in the baking dish then top with remaining cheese.
Bake at 400 degrees's on the top rack of the oven about 30 minutes, keeping your eye on it for the last 5 minutes,
Mac and cheese is done when the top is golden brown and the edges are bubbling.
If after 30 minutes your cheese still needs to brown some more, crank the oven to a low broil and open the oven door slightly and allow the mac and cheese to get golden on top, this will take about 2 minutes. Don't take your eyes off the oven!
Remove the mac and cheese from the oven and allow it to cool for 10 minutes before serving. This will allow the cheese sauce to cool and firm up a bit before serving.