I know it's trendy, but I've always wanted to make Penny's baby food. I love to cook, and it was one of the things that really excited me when I found out I was pregnant. I already had a food processor, and I bought one of the Beaba freezing trays so I could freeze baby food jar sized amounts.
So far, the things I have learned are: steam, bake or cook the baby food plain, with no salt or butter, in as little water as possible if you have to use any. Don't overcook to keep in as many nutrients as possible. Then, put into the food processor and blend! That's it. If you used water to help cook them, you can add some back in to the food processor with the food to make it smoother and add back any nutrients that came out of the food and cooked into the water.
Then, you just put it in whatever you want to freeze it in. I used a tray made specifically for this, but many people just use ice trays. After they're frozen, you can just pop them out, put them in a freezer bag labeled with the food and date, and just grab one and heat it when you're ready for it.
End result: yummy!