Noodles with Butter; Yo baby yogurt mixed with a little flax seed oil; CHicken breast with the skin on; Don't know if he has any nut allergies but Nutella spread is high in fat and delicious(in the peanut butter ailse) My daughter would dip apples, carrots, pretzels in Nutella and peanut butter. There are all kinds of Smoothies in the supermarkets as well; they always look so healthy and full of calories. Maggie was never into that type of texture but you could try?