In a large skillet, heat oil and then toast mustard seeds, cinnamon, cardamom, peppercorns, and green chilies until fragrant.
Then add the onions and cook until soft. Next, stir in ginger and garlic and cook for a few more minutes.
Add tomatoes, turmeric powder, coriander powder, curry powder, chili powder, and salt. Let the tomatoes cook until they begin to break down.
Then, stir in coconut milk and ¼ cup water and bring to a boil.
Simmer until it reduces slightly and starts to thicken.
Taste and adjust salt and consistency with more water, if needed. If it is too thin for your liking, cook more until some of the liquid reduces.
Remove the pan from the heat and drop the eggs in the curry, and cover and let it sit for a few minutes before serving.
Serve with rice or flatbread, if desired.
Pro tip: You can make a big batch of the tomato sauce ahead of time, store it in your freezer and thaw whenever you are ready to eat it. Just reheat and add your hard boiled eggs! To save time, try Eggland’s Best Hard-Cooked Peeled Eggs.