Heat a skillet to medium-high heat, add ground beef, carrots, and the white sections of the green onions. Cook the meat until no longer pink, about 8 minutes.
Stir in the teriyaki sauce, pineapple, rice, salt, and pepper. Once the mixture starts to bubble, turn off the heat and fold in ½ cup of the cheese, stirring until melted.
Fill each pepper half with ¼ cup of the filling and sprinkle with the remaining cheese. Bake the peppers for 10-12 minutes at 350°F. Garnish as desired.