Zesty Spicy Pickled Eggs

4. Add the onion and jalapeño (optional): Add the sliced onion and jalapeño pepper to the jar, if desired.
5. Pour the pickling liquid over the eggs: Pour the hot pickling liquid over the eggs, filling the jar to the top.

6. Seal and refrigerate: Seal the jar tightly and refrigerate the eggs for at least 24 hours before eating. The eggs will continue to pickle and develop flavor over time.