Put the red potato in a pot and add water to cover. Bring the water to a boil over high heat, reduce the heat to medium-high and cook until the potatoes are almost tender, about 10 minutes. Drain and set aside.
Meanwhile, in a large sauce pan over medium-high heat, warm the oil. Add the bell pepper, onion, garlic, scallions and sautué until the onion is translucent, about 2 minutes. Add the plantains, spreading them in a single layer. Reduce the heat to medium and cook, stirring occasionally, until the plantains start to brown and the pepper is soft, about 3 minutes.
Add the potatoes and cumin. Season with salt and pepper and cook, stirring, until the potatoes start to break down, about 1 minute.
Divide the hash among individual plates or bowls. Place an egg on top of each serving of hash, garnish with diced avocado and serve immediately.