• Step 1: In a large skillet or wok, cook the ground beef over medium-high heat, breaking it up with a wooden spoon, until no longer pink, about 5-7 minutes. Drain any excess fat.
• Step 2: Add the teriyaki sauce, brown sugar, garlic, and ginger to the skillet. Stir to combine and let the mixture simmer for 2-3 minutes, until the sauce thickens slightly.
• Step 3: In a small bowl, whisk together the cornstarch and water to create a slurry. Pour the slurry into the skillet and stir constantly until the sauce thickens, about 1-2 minutes.
• Step 4: Remove the skillet from heat and stir in the sesame oil. Taste and adjust seasoning as needed.
• Step 5: Serve the ground beef teriyaki over cooked rice or noodles, garnished with sliced green onions if desired.