Peel potatoes and then cut into small cubes; toss in a bowl with salt, pepper, garlic powder, and olive oil. Mix to coat evenly.

Spray a large skillet with cooking spray and heat over medium-high; add potatoes to hot skillet. Allow to cook until they begin to brown; stir to allow even browning. Continue to cook until all potatoes are fork tender, approximately 15 minutes.

Meanwhile, spray a separate skillet with cooking spray and heat over medium. Whisk together the eggs and water; pour into heated skillet and allow to cook until the sides have become firm. Fold eggs toward the center of the skillet, continue to cook, stirring occasionally to slightly scramble; cook until eggs are no longer runny.

Top eggs with a few slices of avocado; serve with potatoes and grapes on the side.