Preheat the oven to 400°F.
To a small bowl, add olive oil, butter, garlic, oregano, coriander, paprika, cumin, allspice, chili powder, salt, and black pepper. Mix together well.
To a pot filled with water, add the potatoes and salt the water.
Transfer the pot to the stove over medium-high heat and bring it to a boil. Once boiling, cook for about 20 to 25 minutes until tender when poked with a fork.
Drain all the water and take off the heat. Leave the potatoes in the pot for about 5 minutes just so the residual heat can dry any excess water on the potatoes.
Then transfer the potatoes to a non-stick baking tray.
Use the bottom of a flat cup or small plate to smash the potatoes flat. If the potatoes are sticking to the cup or plate, spray a little oil on the surface before smashing.
Add the marinade we made earlier to the potatoes making sure each potato is coated evenly and under the potatoes on the tray so the bottom can get crispy too.
Bake in the oven for 45 to 55 minutes until golden and crispy all around.
Once out of the oven, garnish the top with feta cheese, dill, tzatziki, and pepperoncinis if you would like. All toppings are optional!