Bring large saucepan of salted water to a boil. Add the potatoes and cook them until they are fork-tender, about 15-18 minutes.
Drain potatoes when done and allow them to cool slightly until you can safely handle them.
Generously drizzle olive oil on a sheet pan lined with foil, and set the potatoes in rows. Use a fork, potato masher, or bottom of a cup to gently press down on the potato until it slightly mashes. You want these rustic and chunky; the thinner you smash them, the crispier they'll become.
Drizzle the tops with olive oil and sprinkle with seasoning salt and fresh ground black pepper.
Place them on the top rack of the oven, and bake them for 30-35 minutes, or until crispy, crunchy, and golden brown.
Sprinkle with minced parsley, rosemary or seasonings of choice and serve warm.