Preheat the oven to 450° F. Line a baking sheet with parchment.To make the meatballs. Add the chicken, soy sauce, Gochujang, green onions, ginger, and garlic, to a bowl. Mix until just combined. Coat your hands with a bit of oil, and roll the meat into rounded tablespoon-size balls (will make 15-16 meatballs). Place on the prepared baking sheet. The mix will be wet, but it will firm up in the oven. Add the broccoli to the other side of the baking sheet and toss with 1 tablespoon oil, salt, and pepper. Transfer to the oven and bake for 15 minutes or until the meatballs are crisp and cooked through.Meanwhile, make the sticky Gochujang sauce. In a small pot, combine the soy sauce, honey, rice vinegar, Gochujang, ginger, garlic, sesame oil, and 1/4 cup water. Bring the sauce to a boil for 5 minutes, until the sauce thickens and reduces by about 1/Remove from the heat.Remove the broccoli from the baking sheet. Pour about half the sauce over the meatballs, tossing to combine. Return to the oven for 2-3 minutes, until the sauce coats the meatballs.Combine 2-3 tablespoons of the remaining sticky Gochujang sauce from step 3 with the yogurt. Serve the meatballs and sauce over bowls of rice topped with additional green onions, and sesame seeds. Serve the broccoli on the side.