Heat butter in a sturdy, well-seasoned medium frying pan, preferably cast iron, over medium heat. Add onion and cook, stirring occasionally, until softened and just beginning to brown. Stir in garlic paste, ginger, and chiles. Stir for a moment or two, then add cilantro. Crumble in chips, tossing or stirring the contents of the pan to combine them thoroughly.
Make 4 nests in the surface of the potato-chip mixture—they don't need to be perfect hollows—and crack an egg into each. Pour 1 tbsp. water down the inside edge of the pan to generate some steam. Cover skillet tightly and reduce heat to low. Let eggs steam just long enough to set whites (6 to 8 minutes; gently touch one with a spoon to see if it's done the way you'd like). Season to taste with salt and turn out onto waiting plates.
Note: Nutritional analysis is per serving.