Start by placing 12 duck eggs and 8 chicken eggs in a large pot. Cover with cold water, ensuring eggs are fully submerged. Bring to a gentle boil, cooking duck eggs for 12 minutes and chicken eggs for 9-10 minutes.

Transfer cooked eggs into an ice water bath for 10-15 minutes. Crack shells and peel under running water.

In a medium saucepan, combine 2 cups of white vinegar, 2 cups of water, 2 tablespoons of sugar, and 1 tablespoon of salt. Heat until sugar and salt dissolve, then let cool.

Layer the bottom of clean jars with smashed garlic, followed by crushed red pepper flakes, sliced jalapeños, and sweet red pepper.

Place peeled eggs into prepared jars, packing snugly without overcrowding.

Once brine has cooled, pour it over packed eggs, ensuring they're fully submerged. Seal jars tightly.

Refrigerate sealed jars for at least 3 days to allow flavors to develop.