Heat some olive oil in a large non-stick skillet over medium heat.
Add the sliced potatoes and onions to the skillet and cook until the potatoes are tender, about 10-15 minutes. Stir occasionally to prevent sticking.
In a bowl, beat the eggs and season with salt and pepper.
Once the potatoes and onions are cooked, drain any excess oil from the skillet.
Pour the beaten eggs over the potatoes and onions, making sure they are evenly distributed in the skillet.
Cook the omelette on low heat for about 10-15 minutes, or until the edges start to set.
To flip the omelette, place a large plate over the skillet, invert the omelette onto the plate, then slide it back into the skillet to cook the other side.
Cook for another 5-10 minutes until the omelette is set and slightly browned.
Once cooked, slide the omelette onto a plate, let it cool slightly, then slice and serve warm.
Enjoy!