Preheat oven to 220ºC (425ºF) and grease a large baking sheet with butter or oil. I used a 9-inch x 13-inch (22cm x 33cm).
Use a fork to puncture each potato a few times, creating air holes throughout.
Fill a large pot halfway with water and bring to a boil. Once boiling, add salt.
Add the potatoes to the boiling water, cover with a lid, and return to a boil. Once boiling again, remove the lid and continue to cook for 15-20 minutes or until potatoes can be easily pierced with a fork. Prepare the garlic oil glaze while the potatoes are boiling.
Garlic Oil Glaze
In a small mixing bowl, combine oil, minced garlic, salt, and pepper. Mix until well combined. Set aside.
Assemble & Bake
Once the potatoes are done boiling, remove them from heat and drain off the water using a colander.
Transfer the drained potatoes to the greased baking sheet.
Use the bottom of a glass to press down on each potato, smashing them. A fork can also be used for this step.
Optional: Allow the potatoes to cool for 5 minutes. This helps them dry out slightly, helping them crisp up during baking.
Evenly drizzle the garlic oil glaze over the smashed potatoes. Use a pastry brush for more even distribution, if necessary.
Sprinkle parmesan cheese over the potatoes.
Bake for 35-40 minutes, or until golden and crisp.
Garnish with sliced green onions and serve with sour cream. Enjoy!
Notes
Dairy Free: You can make this with dairy-free shredded parmesan cheese instead of regular parmesan!
Storage: Keep leftover cooked potatoes in an airtight container in the refrigerator for 3-4 days.
Reheating in Air Fryer: Preheat the air fryer to 400ºF (200ºC) and cook for 10-15 minutes, or until heated through.
Reheating in Oven: Preheat oven to 400ºF (200ºC) and bake for 10-15 minutes, or until heated through.
Reheating in Microwave: Place the potatoes on a microwave-safe plate or bowl. Heat in 30-second increments until thoroughly warmed.