Heat oil in pan over medium heat. Fry hard boiled eggs on all sides until brown all over, about 5 minutes. Set aside and pour off all but 1 tbsp oil.
In a food processor or blender, process garlic, onion, bell pepper, and Sambal Oelek into a course paste. Add water and mix well. Pan fry mixture for 2 minutes over medium heat. Stir in tamarind, sugar, salt, ginger, and kecap manis.
Add eggs back in and stir. Reduce heat to medium-low and cook until sauce thickens, about 5 minutes more. Stir to baste eggs in sauce.
To serve, place eggs, either cut in half or left whole, in a small bowl and pour sauce over eggs. Garnish with parsley and fried shallot flakes. Serve at room temperature.