Preheat the Blackstone griddle to medium-high heat (around 375°F).
Add 1 tablespoon of vegetable oil to the griddle and spread evenly.
Add the diced potatoes to the griddle in a single layer. Season with 1/4 teaspoon salt and 1/4 teaspoon black pepper. Cook for 10-12 minutes, stirring occasionally, until potatoes are golden brown and crispy. Remove potatoes from the griddle and set aside.
Add the remaining 1 tablespoon of vegetable oil to the griddle.
Add the diced onion and diced green bell pepper to the griddle. Sauté for 3-4 minutes until softened.
Add the ground beef to the griddle with the onions and peppers. Break the beef apart using a spatula.
Season the beef mixture with garlic powder, smoked paprika, remaining salt, and black pepper. Cook for 6-8 minutes, stirring occasionally, until the beef is fully cooked and browned.
Return the cooked potatoes to the griddle and mix with the beef, onions, and peppers. Spread the mixture evenly.
Sprinkle the shredded cheddar cheese evenly over the beef and potato mixture.
Cover with a large lid or tent with foil for 1-2 minutes to allow the cheese to melt.
Remove from heat and serve immediately.