In a 6-quart crock pot, combine approximately 2 cups of beef stock, ½ cup soy sauce, ¼ cup brown sugar, 2 tablespoons sesame oil, and 4 cloves of minced garlic. Mix well until the sugar has dissolved.

Thinly slice about 2 pounds of sirloin or chuck roast against the grain. Place the beef strips into the crock pot, ensuring they are well coated with the sauce.

Cover the crock pot with its lid and set it to cook on low for approximately 5 hours.

Prepare a cornstarch slurry by whisking together 2 tablespoons of cornstarch with 2 tablespoons of cold water in a small bowl. Stir the mixture into the sauce in the crock pot.

In the last 30 minutes of cooking, add about 4 cups of frozen broccoli florets to the crock pot. Gently stir them into the sauce.

Serve the savory beef and broccoli over a bed of fluffy cooked white rice, garnished with sesame seeds or sliced green onions.