Heat 1tbsp oil in a cast iron skillet or a heavy bottom non stick pan on medium flame. Add onions and jalapeno, cook till the onions are translucent.
Add garlic and chili powder and salt. Cook for 1 minute.
Next add the boiled and chopped potatoes. Lightly mash the potatoes with the back of the spoon and cook undisturbed until the potatoes get nice and crusty.
Mix and cook till all the potatoes form a crust. Add salt, pepper and lime zest. Mix well and serve immediately.