1. For the meatballs: Preheat oven to 375F. Line a baking sheet with parchment paper. Peel and dice onion.
2. Add garlic, onion, mint, parsley, and ground turkey to one bowl.
3. Add salt, black pepper, and eggs to another bowl. Beat eggs and spices until smooth.
4. Add eggs to meat mixture and thoroughly combine with hands.
5. Roll mixture into small ping pong ball sized meatballs. Place meatballs on the baking sheet with enough space so they are not touching.
6. Bake meatballs for approximately 20 minutes.
7. For the sauce: In a small bowl, mix arrowroot with water to make a slurry with no lumps.
8. In a large skillet, add broth and the meatballs. Slowly stir in the slurry and simmer for 8-10 minutes until the sauce is slightly thickened.
9. When the 8-10 minutes are almost up, separate the egg and set the white aside for another use.
10. In a small bowl, beat the egg yolk and lemon juice together thoroughly.
11. Add a few tablespoons of the sauce, one at a time, to the egg and lemon mixture, constantly whisking.
12. Add the egg/lemon/sauce mixture to the meatballs in the sauce, give it a quick stir, and remove from the heat.
13. Serve with a sprinkling of pepper.