In a large skillet, heat the olive oil over medium heat. Add the diced potatoes and cook for about 10-12 minutes, stirring occasionally, until they are golden brown and tender.
Add the diced onion and bell pepper to the skillet with the potatoes. Cook for an additional 5-7 minutes, until the vegetables are softened.
In a bowl, whisk together the eggs, salt, and pepper. Pour the egg mixture over the cooked potatoes and vegetables in the skillet.
Cook the eggs, gently stirring, until they are just set, about 3-4 minutes. Remove from heat.
Sprinkle the shredded cheddar cheese over the top and cover the skillet for 1-2 minutes to allow the cheese to melt.
Garnish with fresh chives or parsley if desired, and serve warm.