Pat the chicken thighs dry and lightly sprinkle each with salt and pepper.
In a large pan over medium high heat add 2 tablespoons of olive oil and then add chicken thighs one at a time. Let cook until skin is browned and they easily release from the pan. Flip and continue to cook until chicken is cooked through, approximately 5-7 minutes per side. Set chicken aside.
Add remaining 2 tablespoons of olive oil to the pan along with the diced onions. Cook until onions are translucent.
Add garlic and orzo stirring constantly. Cook for 1-2 minutes or until orzo begins to brown.
Add chicken broth, asparagus, and about ½ teaspoon of salt. Bring to a boil, cover pan, and reduce heat to a simmer. Cook for approximately 10 minutes or until orzo is al dente and most of the liquid is absorbed.
Add ½ cup of Parmesan cheese to the orzo and stir until melted.
Squeeze one lemon over the orzo, stir, and then add the chicken thighs back to the pan. Sprinkle with remaining parmesan cheese and serve.