Step 1: Heat the olive oil in a large non-stick or cast-iron skillet over medium heat.
Step 2: Add the diced potatoes to the skillet. Cook, stirring occasionally, for 10-12 minutes, or until golden brown and tender. Don't stir too often to allow a crust to form.
Step 3: Add the diced onion and bell pepper to the skillet with the potatoes. Cook for another 5-7 minutes, stirring occasionally, until the vegetables are softened and fragrant.
Step 4: While the vegetables are cooking, whisk the eggs in a bowl with milk or cream (if using), salt, and pepper until well combined.
Step 5: Pour the egg mixture evenly over the potatoes and vegetables in the skillet. Let it set for 1-2 minutes without stirring, allowing the edges to firm up.
Step 6: Gently push the cooked egg from the edges towards the center with a spatula, allowing the uncooked egg to flow to the hot pan. Continue this process until the eggs are mostly set but still slightly moist.
Step 7: Sprinkle the shredded cheese evenly over the top of the scramble. Cover the skillet with a lid for 1-2 minutes, or until the cheese is melted and gooey.
Step 8: Remove from heat and serve immediately. Garnish with fresh chives or parsley if desired.