Heat the olive oil in a flat bottomed saucepan then add the onions. Cook on a gentle heat for about 20 minutes or until the onions are caramelised.
Add the sweet potatoes and stir to thoroughly coat them in the olive oil. Place the lid on and cook for about 45 - 60 minutes or until the potatoes are softened.
Meanwhile pre-heat the oven to 170° and line and grease an 8 inch baking tin.
Take the saucepan of the heat then crumble the feta into the pan, stirring with a metal spoon to combine but not too much as you don’t want the potato and feta to break down.
Pour in the eggs, add the herbs with plenty of seasoning and mix together.
Spoon the mixture into the baking tin, smoothing down so the surface is flat.
Place in the oven and bake for about 40-45 minutes until just browning.
Leave to cool for half an hour the tin before turning out. The tortilla is best served warm.
Serve with the roasted red peppers piled on top.
Notes
*Packets of herbs from the supermarket usually come in 28g bags - these are a perfect size for this recipe.