That sounds great, BWeaves! Didn't know it was a Passover tradition as well. I've seen the tea dyed ones in Chinatown, and Asian recipes, but never saw eggs done in broth. Walter loves to hunt for any broken eggs out of the pot, because as you say, the dye creates lovely patterns. He convinces himself there's a faint onion flavor ...
In old PA families, polishing the eggs was the last step, and while I know a few people who still make onion skin eggs, I know no one else who does this. I was taught by my grandmother, and was deemed the only child old enough and/or careful enough to be around boiling pots of water and hot eggs. When the eggs are still hot/warm (the hotter the better really), you remove them one at a time from the hot dye bath, and lay the egg on either a clean piece of soft fabric (old flannel or T Shirt), or these days, a pad of paper towels, with a dab of Crisco type shortening or vegetable oil, although Crisco works better. The hot egg melts the Crisco into the fabric as you roll the hot egg around to coat it. The eggs get dropped back onto the cardboard egg carton to sit till just warm. Then you go back and rub off the excess Crisco, leaving a nice polish on each egg. Because you polish the eggs while as hot as possible, the Crisco soaks in the shell a bit, and the excess gets removed, so no greasy eggs. Back in the cartons, and in the fridge to cool and await bunnies, kids and hungry husbands
I suspect the Crisco may have been lard a long time ago, and was maybe done to seal the porous surface of the eggs so they'd keep longer in the days before refrigeration. Just my theory, who really knows. My grandmother threw the eggs in the pot with the skins and boiled and let sit; I boil the skins and remove, then cook the eggs ... then ask Walter to do the polishing for me. He thinks this is a treasure hunt for broken eggs to eat, so it works out. He just came in to say out of 5 dozen eggs, he found 3 broken eggs, which he has earmarked for a snack and breakfast. The rest get given out to my family tomorrow, when I will try to find some pearls to wear.