Create the meatballs by mixing the meat, all of the spices, and red onion together. Roll the meat into 1" balls and place on skewers that have been soaked in water.
Place each skewer on a lightly oiled baking pan.
Broil at 500 degrees (keeping the oven door open about 2") for 5-7 minutes, then rotate each skewer and continue broiling for another 5-7 minutes. Ensure that beef is fully cooked.
While the meatballs are cooking, cook the quinoa according to directions.
Slice the cucumbers, tomatoes, red onion, and avocado.
Toss the vegetables, quinoa, and feta together in a large bowl to create the salad.
Serve each bowl by adding 1/4th of the salad and topping with meatballs. Enjoy!