In a medium bowl, whisk together olive oil, lemon juice, minced garlic, oregano, paprika, salt, and pepper. Add the chicken breasts, ensuring they're fully coated. Let them marinate for at least 15 minutes (or up to 2 hours for more flavor).

In a large saucepan, bring the chicken or vegetable stock to a boil. Add the orzo and cook according to the package instructions (about 8-10 minutes), stirring occasionally. Drain any excess liquid and toss the orzo with olive oil, lemon zest, lemon juice, parsley, dill, and Parmesan (if using). Season with salt and pepper to taste.

Heat a grill or grill pan over medium-high heat. Remove the chicken from the marinade and grill for 5-7 minutes per side, or until the internal temperature reaches 165°F (75°C). Let the chicken rest for 5 minutes before slicing.

Plate a generous portion of the lemon herb orzo and top it with slices of grilled chicken. Garnish with extra parsley or dill and serve with lemon wedges.