Heat olive oil in a large skillet over medium heat.
Add the chopped onion and diced carrot to the skillet and cook for 5 minutes, stirring occasionally, until softened.
Add the minced garlic and cook for 1 minute until fragrant.
Add the ground beef to the skillet, breaking it apart with a spatula. Cook until browned and no longer pink, about 7 minutes.
Stir in the frozen peas, salt, black pepper, and dried oregano. Cook for another 3 minutes until peas are heated through.
While the beef mixture cooks, prepare mashed potatoes if not already prepared.
Divide the mashed potatoes evenly onto four plates.
Spoon the ground beef and vegetable mixture over the mashed potatoes.
Sprinkle shredded cheddar cheese on top of each serving while hot to allow it to melt slightly.
Serve warm and enjoy!