1. Bring a pot of water to boil and add 1 tablespoon salt. Cook the potatoes until soft, about 20-25 minutes for small potatoes, 30 minutes for medium. It’s fine if the skin splits.
2. Preheat the oven to 400°F.
3. Drain the potatoes and let them dry in the colander for 5 minutes.
4. Place the potatoes on a baking sheet and smash each one gently with a glass. The thinner they are, the crispier they will get; thicker ones will be fluffy inside.
5. Let them steam dry for 5 minutes on the tray, then drizzle generously with olive oil and sprinkle with salt. Flip the potatoes, coat with more oil, and season again.
6. Bake for 30-40 minutes, checking for crispiness, but ensuring they don’t burn.