01 -
Scrub the potatoes and drop them into a pot of salted cold water. Bring to a boil and simmer for 15 to 20 minutes until a fork slides in with no resistance. Drain well and let them steam dry for about 5 minutes.
02 -
Arrange the potatoes on a parchment-lined baking sheet. Press each one with the bottom of a glass or a masher until it is about a quarter-inch thick. Let them sit for another 5 minutes so surface moisture evaporates.
03 -
Brush the smashed potatoes generously with melted butter. Sprinkle kosher salt, garlic powder, and black pepper over the tops. Bake at 425°F for 20 minutes, then flip each potato and bake for another 20 minutes until both sides are deeply golden.
04 -
Scatter diced jalapeños across the crispy potatoes, then pile on the shredded cheddar. Return the sheet to the oven for 3 to 5 minutes until the cheese is fully melted and bubbling.
05 -
Stir together sour cream, dry ranch seasoning, and jalapeño powder in a small bowl. Taste and adjust if you want more kick.
06 -
Slide the potatoes onto a platter and set the dip alongside. Serve immediately while the edges are still crackling and the cheese is soft.