Cut the chicken into 1½–2-inch cubes and toss with the dried basil, oregano, paprika, salt, and pepper to coat evenly.
Heat the olive oil in a large skillet over medium-high heat. Add the seasoned chicken and cook 5–7 minutes until mostly cooked through and lightly browned, then transfer to a plate.
Reduce heat to medium and add the butter to the skillet. Sauté the minced shallots and garlic for about 2 minutes until fragrant and softened.
Add the orzo to the skillet and stir constantly, toasting it until lightly golden, about 2–3 minutes.
Pour in the chicken broth, lemon juice, and lemon zest. Reduce heat to medium, stir occasionally, and simmer until the orzo is tender and has absorbed most of the liquid, about 10–12 minutes.
Return the cooked chicken to the skillet and add the chopped spinach. Stir and cook until the chicken is fully cooked through and the spinach is wilted, about 2–3 minutes.
Remove from heat, sprinkle with shredded Parmesan cheese and additional lemon slices if desired, then serve.