Nothing could be sweeter and have more texture than roasted beets. I've been making them for Kenya since he got his first teeth in and he has always loved them. It was so funny to watch him eat these when he was teething because he would roll them around in his mouth, massaging his gums.
Another fun part about beets is that they come in so many colors. Kenya always seems to be taken with foods that are bright in color or cut in interesting shapes. My personal favorites are the orange/yellow ones, but the "candy cane" beets (with their white and red stripes) have a uniquely sweet flavor. Red beets, usually the easiest to find are great too, but beware that the red color can get all over your hands (and your baby's which in turn will get all over you).
The recipe for beet puree is the same as these roast beets except that you cut them into little bite size squares. When Kenya and I take a walk and he's in the stroller, instead of filling his little cup with cheerios, I put this sweet treat inside. Give it a shot.