Pat 1 ½ pound boneless skinless chicken breast dry and cut into 1½–2-inch cubes. In a bowl, toss the chicken with 2 teaspoons dried basil, 1 teaspoon dried oregano, 1 teaspoon paprika, 1 teaspoon salt, and ½ teaspoon pepper until evenly coated.
Heat 2 tablespoons olive oil in a large skillet over medium-high heat. Add the seasoned chicken in a single layer and cook 5–7 minutes, turning occasionally, until the pieces are lightly browned and mostly cooked through. Remove the chicken from the skillet and set aside.
Reduce heat to medium. Add 1 tablespoon butter to the skillet. When the butter has melted, add 2 minced shallots and 2 cloves minced garlic and sauté about 2 minutes, stirring, until the shallots are softened and fragrant.
Add 1 cup orzo to the skillet and stir constantly for 1–2 minutes, until the orzo is evenly toasted and lightly golden.
Pour in 3 cups chicken broth, 2 tablespoons lemon juice, and 2 teaspoons lemon zest. Stir to combine and bring to a gentle simmer. Reduce heat to medium-low and cook, stirring occasionally and scraping the bottom of the skillet, until the orzo is tender and most of the liquid is absorbed—about 9–12 minutes.
Return the cooked chicken to the skillet and add 2 cups chopped baby spinach. Stir and cook 2–3 minutes more, until the chicken is fully cooked through and the spinach is wilted (internal temperature of chicken should reach 165°F / 74°C).
Remove from heat and sprinkle with shredded parmesan cheese to taste before serving.