Preheat your oven to 400 degrees.

Prepare a sheet pan with some parchment paper and set aside.

Peel your sweet potato and dice it up. Try to keep the dice all the same so that they cook evenly and all at the same time.

Pour potatoes into a bowl and drizzle the olive oil over them.

Stir the potatoes around with a wooden spoon until the olive oil is evenly distributed.

Sprinkle in the rosemary, salt and ground pepper. Give it all another stir to make sure that all the spices are evenly distributed.

Pour potatoes onto your sheet pan and spread into one layer.

Pop in the oven for 15 minutes.

Then pull the sheet pan out and with a spatula flip the potatoes as best you can.

Put the sheet pan back in the oven for another 20 minutes and when that time is up, they are done.