Heat a large skillet over medium heat. Add the ground beef and minced garlic, breaking the meat into crumbles as it cooks.
Cook the beef and garlic until the meat is no longer pink and cooked through, about 4–5 minutes. Drain excess fat if desired.
In a small bowl, whisk together the brown sugar, soy sauce, sesame oil, ground ginger, crushed red pepper flakes, and ground black pepper until smooth.
Pour the sauce over the cooked beef and stir to combine. Let the mixture simmer for 1–2 minutes so the flavors meld and the sauce slightly thickens.
Divide the cooked rice between four sealable containers, using about 1/2 cup rice per container.
Top each portion of rice with about 1/2 cup of the Korean-style beef and 1/2 cup steamed broccoli florets.
Seal the containers and refrigerate until ready to eat. Reheat in the microwave before serving if desired and garnish as you like.