Preheat the oven to 425°F (220°C) and line a baking sheet with parchment paper or lightly grease it.
Place the potatoes in a pot, cover with salted water, and bring to a boil. Cook until fork-tender, about 15 to 20 minutes.
Drain the potatoes and let them cool slightly. Arrange them on the prepared baking sheet.
Use the bottom of a glass or a potato masher to gently smash each potato until flattened but still intact.
Drizzle with olive oil and season with salt, pepper, and garlic powder if using.
Bake for 20 to 25 minutes, then flip if desired and bake 5 to 10 minutes more until crisp and golden brown.
Garnish with parsley and serve hot.