Preheat the oven to 375 degrees.
For those sweet potatoes, you will want to scrub them, peel, and then slice very thin. I use a mandolin.
Put them in a large bowl with plenty of room to mix around.
Pour the melted butter and coconut or olive oil on top.
Add in the fresh chopped rosemary and Parmesan cheese.
Lastly sprinkle with salt and pepper to taste.
Mix well with your hands, making sure that both sides of the sweet potatoes are coated.
Stack up the sweet potatoes in the muffin tins. Fill all the way to the top as they will shrink down a bit once cooked.
Bake for about 45 minutes, watching for the edges to turn golden brown and crispy.
Remove from the oven and let cool for a few minutes before you move them to a serving platter.