Preheat oven to 425°F. Line a baking sheet with foil and grease lightly with cooking spray, set aside.

To make the meatballs, in a large bowl, mix together the beef, bread crumbs, egg, garlic, ginger, sesame oil, sriracha, scallions, salt and pepper until evenly combined. Try not to over-work the mixture or else you'll end up with tough meatballs. Roll about 2 tablespoons or so of the mixture in between your palms and place on the prepared baking sheet. Continue rolling and shaping the remaining mixture until all the meatballs are done, leaving about a few inches of space in between each. Bake until golden brown and crispy, about 18 to 20 minutes, flipping over halfway through.

In a large bowl or measuring cup, whisk together 2 tablespoons sesame oil, beef stock, soy sauce, brown sugar, cornstarch, and red pepper if using, and set aside.

In a large skillet, heat the remaining tablespoon of sesame oil over moderate heat. Once hot, add the broccoli and sauté for about 5 minutes or until bright green. Add in the meatballs and stir in the sauce. Reduce heat to low, cover with a lid, and cook until the sauce has thickened, about 8 minutes. Give it a stir and top with sesame seeds and scallions. Serve with rice and enjoy!