Heat olive oil in a large skillet over medium heat.
Add diced onions and bell peppers; sauté until soft.
Stir in minced garlic and cook for another minute.
Add ground beef; cook until browned, breaking it apart as it cooks.
Drain excess fat from the skillet.
Mix in diced tomatoes, olives, raisins, and cumin.
Season with salt and pepper to taste.
Reduce heat and let simmer for 15-20 minutes.
Stir occasionally, allowing flavors to meld.
Serve hot over rice or with tortillas.