Boil the egg. Place the egg in cold water in a pot and bring to boil. When the water is boiling set the timer to 8 minutes. Drain, wait few minutes and remove the eggshell.
Peel the sweet potato and chop it in small pieces. Steam the sweet potato for 8 min.
In a small serving bowl place two tablespoons of steamed sweet potatoes and smash them with a fork, add the avocado, smash, add the egg yolk, smash.
For a more liquid consistency add few tablespoons of the thinning liquid of your choice (baby formula, breastmilk, hot water).
For toddlers or for a baby led weaning approach simply slice the egg white. Spread the puree on a slice of bread, and sprinkle the egg whites on top. Slice in small bites to serve.