Start by preparing your ingredients: slice the shallots, garlic cloves, and red chilies as thin as you can. Then, chop the coriander.
Put the quail eggs into a large pan of water and bring them to a boil. As soon as the water is simmering, time the eggs for 3 minutes. Cool the eggs down under cold running water, then proceed to peel them.
Take the sugar, fish sauce, and tamarind and mix them together in a pan. Heat them up gently and stir until the sugar has dissolved. You can skim the top if you need to. Also, check the taste. If it's both sweet and sour then it's perfect. If not, adjust it with extra sugar, fish sauce, or tamarind.
In the meantime, take a large frying pan or a wok and pour sunflower oil, about two finger's depth (5cm). Once the oil is simmering add the shallots, garlic, and chilies. Fry these for about 1 minute so they turn golden and crispy.
Take them out and place them on kitchen paper to remove the excess oil. This can be done hours ahead if you want. Next, you will fry the boiled quail eggs for about 3-4 minutes. You'll know they're ready when the outside turns golden brown. Remove them from the oil and put them on kitchen paper.
Take a bowl and combine the coriander with the crisp chili, garlic, and shallots. Mix them well and pour the sauce and coriander over the eggs and serve.