Thanks for the previous suggestions to try frozen mixed
veggies and baby foods. My budgie likes tomatoes, strawberries,
canteloupe and pears. I just wash them well and give him a slice big enough to "stand up" by itself. Then he just nibbles away, takes what he wants and I throw it out a few hours later.
He absolutely loves cooked, plain spaghetti and dry
grapenuts cereal, which I sprinkle on the kitchen table or near his food dish on the floor of his cage.
Years ago I had a budgie that loved grated carrots. His face would actually turn orange because he was so excited and
messy when eating them.