these are a huge favourite in our home.
Peel and cut up sweet potatoes into the size of fries... place in a bowl with a bit of olive oil and herbs such as basil and oregano. Toss together then empty out onto a baking stone or tray. Put in the oven on 350 degrees celcius for about 40 minutes or until fries are tender. They will disappear before you know it!!
If basil and oregano are not favourites, try experimenting with other herbs and spices.
cheers!