Place the potatoes in a large saucepan, cover with cold water and add 1 tablespoon salt. Bring to a boil over high heat and cook until the potatoes fall apart when a fork is inserted, 20 to 25 minutes. Drain well.
Heat the butter over medium heat in a large saute pan. Add the onion and jalapeno and cook until soft. Add the garlic and cook for 30 seconds. Stir in the ancho chile powder and stir until combined. Add the potatoes, salt and pepper and toss the mixture, slightly mashing the potatoes with a metal spatula. Press the potato mixture into one even layer and cook until golden brown on the bottom. Turn over and gently mash again into an even layer and cook until the bottom is golden brown. Stir in the cilantro and lime zest and transfer to a bowl.