Ah yes...the "tan food" child. Not one other color in the mix. That was my son as well. Try mixing pureed butternut squash in with the mac & cheese, and/or adding some "good cheese" to the boxed mix. Start small and work your way up. You can buy the squash in the frozen section and just cut off a piece with a warm, sharp knife, then melt it in with the cheese. When I steamed vegetables for us (broccoli, spinach, beans etc.), I drained off that green water into a pitcher, cooled it, and froze it either in freezer containers or ice cube trays. Then I used it for anything that absorbed all the water (rice, couscous). Don't waste it on pasta where all the water isn't absorbed.
I also put all kinds of stuff in pancakes and French toast. I used protein powder and soy milk powder in both, and I used really "holey" bread for the FT so it would absorb a lot more in the nooks & crannies. I put cinnamon on top - he liked that. Then I added cinnamon to the batter or sprinkled it on while the toast was cooking. Pretty soon "cinnamon brown" toast covered up the fact that I was using whole grain bread. I like Nature's Promise Flax & Grain from Stop & Shop - lots of holes! In the pancakes, I was even more relentless - finely chopped broccoli (I know it's weird but he ate it!) and anything else I could chop up, plus wheat germ and flax meal. I also put a lot of great things in lasagna - don't know if your child will eat that yet but there's a lot you can do with spinach and tofu and cottage cheese in there!
You could also try falafel - my son ate that, surprisingly - I guess because it was tan! I used the mix (you might have to go to the health food section of the market) but cut the spiciness with added wheat germ, flax meal (ground flax seeds), even whole wheat bread crumbs plus extra "veggie water" as described above. I fried them up quickly in canola oil or light olive oil (or a mix) just to crisp them up, and then finished them in the oven.
Have you tried giving her things to dip in other things? Kids sometimes like that. Carrot strings instead of carrot sticks make chewing easier. Make a light cream cheese dip by microwaving it briefly to soften it. You can try ranch dressing too. There's also a dip you can make with whipped cream or whipped topping, instant pudding (lemon, raspberry, whatever she might like) and milk. It's good for dipping fruit. Maybe fruit chunks on skewers or fancy toothpicks would interest her? Or even let her dip it in chocolate? A small amount helps get the fruit in!
I have heard many times that it takes an average of 10 times for a child to try a new food that is introduced and for them to develop a taste for it.
In the last few years I found a great children's supplement that comes in a vanilla or chocolate flavor - mix with any liquid including water - makes up for all the missing nutrients in food. If you are interested I can help you with that.
Meantime, you are doing the right thing, introducing her to foods and not making special meals. You can't make her eat but it sounds like she is learning good manners. Stick with it!