Or more, depending on how long it takes you to weight things out.
First attempt I weighed nothing and eyeballed everything. Somehow it was the best Mac n'Cheese I'd ever had; likely because it doesn't use any oven time. You're not overcooking the pasta, drying things out ect.

Recipe (for one)

75g Macaroni or similar Pasta (dry weight)
75g Grated Cheese
150ml Whole Milk
1/2 Cup Dried Breadcrumbs
2tbsp Oil
1tbsp Plain Flour
Salt and Pepper to taste
(Optionally) a sprinkling of Paprika and Chilli Powder for some zip

1. Put one small saucepan of water on medium heat and bring to a simmer. At the same time put a deep, medium-sized frying pan on medium heat along with one tablespoon of Oil. Once your water is bubbling, drop your Pasta in and cook for ten minutes.

2. In those ten minutes you're given plenty of time to make the sauce. Add one tablespoon of Flour to the Oil, combine into a loose roux and cook until it turns a dark blonde colour - about two minutes. Whisk the Milk in gradually, letting the mixture thicken up each time before adding more liquid until you've spent all your Milk.

3. Add the Cheese the same way you added the Milk; mix in small fistfuls at a time until fully incorporated and add Salt, Pepper and any desired spices to taste. If you are adding spices it's a good idea to let them cook in the sauce for a minute or two to let the flavours bloom before tasting.

4. Bring your frying pan down to a low heat and let the sauce simmer with what time you have left. Stir occasionally to keep it from burning.

5. Drain your Pasta once it's finished and combine it with the Cheese Sauce in the same saucepan you just drained. Leave it on a very low heat while you put on another frying pan - medium heat - along with one more tablespoon of Oil. Add the dried Breadcrumbs and fry for a couple of minutes to turn them golden brown.

6. Transfer the Macaroni to your dish, then top with the Breadcrumbs and serve.

Notes
- So I've started using Oil instead of Butter when I'm making my Roux. I've found it a lot easier to cook out the 'raw flour' taste this way, haven't had any trouble with lumps ect.
- I saved myself from breaking out another frying pan by using the same non-stick pan I made my cheese sauce in.