heat oven to 425 F and line a large baking sheet with parchment
add potatoes and 1 tbsp kosher salt to a large pot and cover with water
bring to a boil then simmer until potatoes are fork tender 15 to 20 minutes
drain well and let potatoes steam dry in the colander 5 minutes.
Smash and roast
transfer potatoes to the baking sheet spaced apart
smash each potato to about 0.5 inch thick using a flat bottom cup
brush or drizzle with olive oil and melted butter then season with garlic powder pepper and salt to taste
roast until deep golden and crisp 25 to 30 minutes flipping once halfway if desired.
Add cheese
sprinkle cheddar and parmesan over the potatoes
return to oven until cheese melts 5 to 8 minutes
optional broil 1 to 2 minutes for extra browning while watching closely.
Serve
top with chives and parsley and serve hot with sour cream if using.
Notes
1. Use baby red potatoes or fingerlings if needed. For extra crispness steam dry potatoes well and use enough oil. Swap cheddar for mozzarella Monterey Jack or gruyere. Add cooked crumbled bacon or sliced jalapenos for a loaded version