Don't Actually Blow It!
While such egg shells are often described as "blown" eggs, from a food safety perspective, blowing into an egg isn't a good idea. Doing so could result in foodborne illness, says Karen Blakeslee, Kansas State University Research and Extension rapid response center coordinator. She offers these tips:
1. Wash egg in warm water and pat dry with a paper towel.
2. Sterilize a sewing needle with hot soapy water or a water-and- bleach solution.
3. Use the sterilized needle to poke a hole in the narrow end of the egg.
4. Sterilize a larger needle (such as a yarn needle) or an ice pick and poke
a larger hole in the wide end of the egg, making sure that both the shell
membranes and yolk are broken.
5. Hold the egg over a bowl or food storage container. Press the bulb of a turkey baster against the small end of the egg to push air into the egg and contents out the other end.
6. Rinse empty shells with cold water and allow them to dry before decorating.
Use the contents from the eggs immediately in a recipe that will be fully
cooked, such as a casserole, egg custard or baked item. To save the eggs for
later use, beat until blended and pour into freezer containers; label and
date. Thaw in the refrigerator and use promptly.