Baby food

I know some moms are starting now at 4 months and others are starting at 6 months. We started baby food at 4 months as he is showing the signs of being ready. I make my own baby food and was giving the ok by his doctor. We decided to start now to get him use to foods as when he turns 6 months and able to sit up unassisted we will start baby led weaning. To the moms that have started baby food what was the first one you tried? We tried sweet potatoes and he loves them.