Prepare scallions, mint, and lemon. Combine with peas and set aside.
In a large pot, heat the olive oil over medium-high heat. Season the chicken with salt and pepper. Add to the pot and cook, turning occasionally, until golden, 6 to 8 minutes. Transfer to a plate.
Add the chicken broth and 2 cups water to the same pot and bring to a simmer. Add the tortellini and cook according to package directions.
Shred chicken.
Once the tortellini has finished cooking, remove from the heat and stir in the shredded chicken, peas, scallions, lemon peel, lemon juice and mint. Season with salt and pepper.