It's important when introducing solid food to your baby that you are making sure to offer her foods that represent a well-balanced diet. I'll admit: sometimes I forget about protein. I am better with Buttercup than I am with myself. I'll find myself going a few days without making a conscience effort to eat protein of some sort. The solution usually ends up being tuna. Firstly, tuna has those super Omega-3s. Secondly, I get it free from WIC (a government nutritional supplementation program for women, infants and children). Thirdly, it's easy - no cooking required!
One day I was making myself some tuna salad for a sandwich and thought I'd give some to Buttercup to try. I left the pickle relish out, since it's mostly salt. So, hers just had tuna and some mayo (I use the olive oil variety). I plopped about a quarter cup onto her tray and she happily shoveled it into her mouth. I don't know why I didn't think of this sooner, but we'll definitely be keeping this as a protein emergency staple.
PROS: easy protein option
CONS: gives baby fishy breath