Set oven to 400℉.
In a large bowl, mix together meatball ingredients until combined. Spoon into 1 tablespoon balls and place in a 9x13 (or equivalent) baking dish spaced so that the meatballs are not touching.
Bake meatballs at 400℉ for 20-25 minutes, or until the internal temperature reads 165℉. Prepare the soup while the meatballs are cooking.
In a large pot, add the olive oil, garlic, carrots, and ½ onion. Saute until onions are translucent (3-5 minutes). Add garlic powder, onion powder, and chicken broth. Bring to a boil.
Add the orzo and cook according to package directions for al dente. In the final minute of the orzo cooking, turn off the heat and add the spinach, thyme, lemon juice to the pot and stir to combine.
Remove the meatballs from the oven once they are ready and either add to the soup pot or to individual bowls and serve the hot soup over them.