Preheat the oven to 400°F. Grease a muffin tin with cooking spray.
In a medium bowl, combine the hash browns and shredded cheddar cheese.
Divide the hash brown mixture among the 6 muffin tin cups (they will be very full but will shrink as they bake), pressing the potatoes into the
bottoms and up the sides of each cup.
Bake the hash brown cups for 25 minutes then remove them from the oven and using a dry measuring cup or spoon, push down the centers of the muffins to make enough room for the eggs. (I sprayed the bottom of the 1/3 measuring cup with cooking spray so it would not stick to the potatoes)
Crack an egg into each cup then top each egg with salt and pepper.
Return the hash brown cups to the oven and bake them an additional 10 to 12 minutes or until the eggs reach your desired doneness.
Remove the hash brown cups from the oven and let them cool for at least 10 minutes in the muffin tin before running a sharp knife around the edges to release them. Top the hash brown cups with the chopped fresh chives and serve.