Mac and cheese!

if you're willing to try something a little bit out of the box, i will humbly suggest the following: quinoa mac and cheese. seriously, try it.

http://www.salmonatseven.com/2012/07/11/quinoa-mac-and-cheese/

For 145 calories I make 1/2 cup whole meal pasta and cook for 6 minutes with 1 cup of water. I add 1/2 cup of spinach from the garden for the last minute . I drain this and put in a bowl with fresh cracked pepper and 20g mozzarella grated cheese and zap in the microwave for. 30 seconds.
See what you think

You can make it with a cornflour sauce instead of a roux. Instead of starting with flour and butter, you heat most of the milk in the pan. Mix a bit of the milk with the cornflour, then stir it in when the milk is close to boiling (stir quite quickly and get to all corners of the pan so that it doesn't go lumpy). Add grated cheese - I would use strong, mature cheddar, because you don't have to use so much to get the flavour, and seasoning helps to add flavour too, e.g. salt, pepper, mustard, paprika. Mix with hot cooked macaroni.

Here's an example of a cornflour sauce recipe http://www.skinnyblog.co.uk/2010/08/cheese-sauce-made-with-cornflour-and-has-no-butter/ . I believe cornflour can also be called cornstarch.

You can also use a low fat soft/spreading cheese like Philadelphia. Mix/melt that with the hot pasta in the pan, and add a little grated cheddar and seasoning for flavour (and a little milk if it's too thick). It's nice, but to me, it doesn't taste as traditional as the cornflour sauce technique.

I also like to bulk out macaroni cheese with green veg. I think it improves the look and taste. Broccoli and peas are particularly good.

Edit: I misread and didn't realise you were looking for a clean eating version. I don't know if you are able to eat cornflour or flour! If you can't use flour/thickeners you can make a lovely, but high fat, pasta sauce by getting a good quality strong-tasting cheese (e.g. pecorino, etc.) and melting it in double cream (yes, cream) and mixing that with cooked pasta, salt and pepper, and top with some fresh chopped herbs - chervil is nice, or chives or parsley. This is DELICIOUS! But obviously not low-cal! Or you could thin down cream cheese with milk and use that.

http://www.cleaneatingmag.com/Search-Results.aspx?recipeQuery=macaroni and cheese
this is where I get most of my recipes from then I tweak from there :-)

You know you can still eat your mac and enjoy it just the way you like to prepare it just eat it in moderation
Assuming you make it fresh and bake it so instead of making a big ol pan of it make a smaller pan of it and enjoy it over a few days and heck if its because you like to eat more of it just add some good cardio like eliptical or zumba for the day to earn extra calories so you can enjoy as much as you want - if your gonna eat 800 calories in mac earn an extra 800 calories in exercise