1 onion, sliced into rings
1 cup distilled white vinegar
1 cup water
10 cloves garlic, peeled
¼ cup white sugar
Place eggs in a medium saucepan and cover with cold water. Bring water to a boil and immediately remove from heat. Cover and let eggs stand in hot water for 10 to 12 minutes. Remove from hot water, cool, and peel. Place eggs and onion into a 1-quart jar. Combine vinegar, water, garlic, and sugar in a medium saucepan; bring to a boil. Remove from heat and allow to cool, about 15 minutes. Pour vinegar mixture over eggs and cover with a lid. Refrigerate for 1 week before serving.