Heat olive oil in a large skillet over medium-high heat for 60 seconds until shimmering. Add ground beef and cook 8-10 minutes, breaking it apart with a wooden spoon as it browns. Drain excess fat and set beef aside on a clean plate.

In the same skillet, add diced onion and cook 3 minutes until softened and translucent. Stir in minced garlic and cook 1 minute until fragrant, then add sliced bell peppers to the beef peppers skillet.

Sauté peppers and onions together 4 minutes until they begin to soften but remain crisp-tender. This timing preserves their bright colors and slight crunch that contrasts beautifully with the tender beef.

Return the cooked beef to the skillet, then add beef broth, tomato paste, soy sauce, Worcestershire sauce, paprika, salt, and black pepper. Stir thoroughly to combine all ingredients and simmer for 5 minutes until flavors meld.

While simmering, whisk cornstarch and water together in a small bowl to create a slurry. Pour the slurry into saucy beef and peppers, stirring constantly 1-2 minutes until sauce thickens and coats the beef and vegetables evenly with a glossy sheen.

Remove from heat and taste for seasoning—adjust salt or soy sauce as needed. Top with chopped green onions and fresh parsley for brightness and color contrast.