1️⃣ In a small bowl, mix soy sauce, beef broth, sugar, and cornstarch. Set aside.
2️⃣ Heat 1 tbsp oil in a large skillet over medium-high heat. Cook broccoli for 3–4 minutes, remove and set aside.
3️⃣ Add remaining oil, cook beef slices until browned, about 3–4 minutes.
4️⃣ Add garlic and cook for 30 seconds.
5️⃣ Return broccoli to skillet, pour sauce over, and cook until sauce thickens and everything is heated through, about 2–3 minutes.