Peel and cube the potatoes into 1/2 inch pieces.

Place the cubed potatoes in a large saucepan and cover with water.

Bring the water to a boil.

Reduce the heat to medium; cover the saucepan and cook for 12-15 minutes, or until the potatoes are tender.

Drain the cooked potatoes.

In a large bowl, combine the shredded cheddar cheese, condensed cream of chicken soup, sour cream, melted butter, chopped green onions, salt, and pepper.

Gently stir in the drained potatoes to combine with the cheese mixture.

Transfer the potato mixture to a greased 13x9 inch casserole dish.

Bake the casserole, uncovered, at 350 degrees Fahrenheit for 40-45 minutes, or until bubbly and golden brown.

Let the casserole stand for 10 minutes before serving.