I'll be the weirdo. I thought soup was one of the easier things to eat while nursing (still do!). Also yogurt but that's not something you'd probably make for a new mom, and homemade mac and cheese with extra-sharp cheddar.
I appreciated the lasagnes the most. Other casseroles are easy to eat one-handed too. My friend made me a pretty good chicken casserole, you can PM me for the recipe if you're not averse to using Campbell's soup (cream of celery or cream of chicken) and aren't a vegetarian. There's a spinach-and-rice casserole in the Moosewood book that's delicious. And I do a vegetarian one with lentils, spinach, chopped tomatoes, feta and seasonings that I absolutely love! You can serve it over brown rice, too.
Oh, and my sister's boyfriend made us spaetzle and lentils the night we got home. Delicious and easy to eat!