Mix salt, sugar and spices in medium bowl until well blended.
Spread half of the seasoned salt mixture in 3 glass baking dished, make 36 indentations into the salt mixture with the back of a spoon. Place an egg yolk into each indentation. Gently cover yolks with remaining salt mixture. Cover with plastic wrap, leaving one corner open for moisture to escape. Refrigerate 4 days.
Preheat oven to 170°F. Remove egg yolks from salt mixture and carefully rinse in water. Place yolks on rack in small rimmed baking sheet.
Bake 3 hours.
*Egg Safety and Handling: Consuming raw or undercooked eggs may increase your risk of foodborne illness. Wash hands with soap and warm water before handling eggs and at every step of egg preparation.
Serving Suggestions: Serve cured egg yolks with congee, or grate, shave or crumble over pasta, noodles, rice, salads, vegetables and soups.