Preheat oven to 425 degrees Fahrenheit. Boil potatoes in a large pot of water until fork tender. Drain and let sit in the colander for about 5 minutes.

While potatoes are cooling, whisk together olive oil and half of the truffle oil in a small bowl.

On a baking sheet lined with parchment paper, spread out the potatoes. Smash potatoes using a heavy glass such as a mason jar.

Brush each smashed potato generously with the oil mixture.

Next, season the potatoes with desired amount of salt, pepper, and the chopped sage. Sprinkle with the parmesan cheese.

Bake the potatoes for 8-10 minutes until crispy. To serve, drizzle with remaining truffle oil and serve with additional parmesan cheese.