I have an almost two year old and just like every Mom, I am concerned about what he eats.
I am big on whole grains,since they contain a lot of protein, vitamins (especially B-vitamins,) and keep you fuller longer because of their low sugar content. So I buy quinoa (it's a complete protein, by the way,) buckwheat, millet, amaranth, wild and brown rice. I cook those according to the package instructions and it takes 10-30 minutes. Sometimes, I make one grain and we eat it fresh for a few days and sometimes I make a bunch of them and freeze them for later.

I also sautee whichever vegetables I have with some organic extra virgin olive oil and Bragg's amino acids (it's like soy sauce, but healthier) and sometimes add beans or tofu, and sometimes do not. I take toddler plates I bought in Babies R Us and put the grain on one side and the veggie mix on the other side. Depending on how many plates I make, I either refrigerate or freeze them. I also take leftover veggies and mix them with Quinoa pasta (this one is my kid's favorite.) I buy this pasta variety at a health food store -it contains no wheat.

I also make juices for my kid, when I have the time. The key is to stick as many veggies as possible into the juice. The way I do it is by putting a couple of sweet apples in there, to hide the taste of all the celery and the broccoli I put in there for health purposes. Putting the vegetables in the blender, instead of a juicer, preserves them whole, which is better. unfortunately, I don't have a good blender right now.

I am also big on dried fruit. Since the kid never eats any candy or cookies, he thinks that dried fruit IS candy. The figs and the dates are his favorite. If you really have some extra time, then stick some figs, dates, prunes and nuts into the food processor, form little balls and roll those in shredded coconut. I also give my son apple slices and banana pieces as snack foods. Surprisingly, he enjoys snacking on boiled eggs, which have all the protein he needs to grow, so I don't object!

Another thing is smoothies.
I stick things like spirulina powder in my little man's smoothie (spirulina is a complete protein, all amino-acids, super digestible. It also has iron, vitamin C, calcium and other good stuff.)  I take a banana, any berries I got, spirulina powder, a bit of rice milk, ice cubes and stick it all in the blender. I also put a cucumber in his berry/banana smoothie sometimes. He doesn't notice. I also put almond butter in smoothies for protein, but it can be used to make the smoothies extra yummy. Also, , if your kid doesn't want to sit down for a meal, smoothie is a great a nutritious alternative to one.
Another little trick I created once out of despair was a blended pasta sauce. He went through this phase where if there was pasta on the plate, he wouldn't eat any vegetables with it. So, I'd saute a bunch of veggies with a lot of tomatoes, blend the mixture in the blender and pour it over the pasta. He thought it was liquid, but mama knew that it contained kale and broccoli and carrots and tomatoes!