Boil the eggs: Place eggs in a pot and cover with cold water by about an inch. Bring to a gentle boil over medium-high heat, then reduce to a simmer and cook for 10 minutes. Don’t boil aggressively or the whites can toughen.

Shock and peel: Transfer eggs to an ice bath and let them chill for 10–15 minutes. Tap each egg around its middle, roll gently to crack, and peel under running water. Aim for smooth, intact whites.

Prep the jar: Clean your jar and lid with hot, soapy water and rinse well. For best results, pour boiling water into the jar, let sit a minute, then empty and air-dry. This helps keep things tidy and reduces off flavors.

Make the brine: In a small pot, combine vinegar, water, sugar, salt, garlic, onion, peppercorns, mustard seeds, bay leaves, and any optional heat or herbs. Bring to a simmer over medium heat, stirring to dissolve sugar and salt. Simmer 2–3 minutes to infuse flavors.

Cool slightly: Turn off the heat and let the brine rest for 5 minutes. You want it hot, but not boiling when it hits the eggs. This helps preserve texture.

Pack the jar: Add the peeled eggs to the jar, layering with the softened onion and garlic. Pour the hot brine over the eggs, making sure everything is submerged. Leave about 1/2 inch of headspace at the top.

Seal and chill: Wipe the rim, close the lid, and let the jar cool to room temperature on the counter for about 1 hour. Then refrigerate.

Wait for flavor: For best taste, wait at least 3 days before eating. Peak flavor usually lands between day 5 and day 10. The longer they sit, the deeper the flavor.

Serve: Enjoy cold, straight from the jar, or slice onto toast, grain bowls, salads, or charcuterie boards. Sprinkle with black pepper or paprika for a simple finish.