You can use almost anything edible in your kitchen to color eggs, Chiarello has found. Place eggs in a deep, non-reactive saucepan. Add your coloring ingredient, then cover with a quart of cold water and 2 tablespoons of white vinegar to fix the dye. Gently simmer the eggs for 20 minutes or up to 3 hours, until you like the color. For a beautifully delicate, shattered look, remove a few eggs and gently roll each in a soft towel.
Return eggs to the pot for another half-hour.
You can eat the eggs so long as you haven't used anything toxic in the dye. If you don't eat them right away, you can store them, unshelled and with uncracked shells, in the refrigerator for 2 to 3 weeks.