Heat olive oil in a large, deep skillet over medium-high heat. Add diced chicken and cook until browned and cooked through, about 5-7 minutes. Remove chicken from the pan and set aside.
Reduce heat to medium. Add diced onion to the same pan and cook until softened, about 3-4 minutes. Stir in minced garlic and cook for 1 minute more until fragrant.
Add Arborio rice to the pan and stir for 1-2 minutes until the edges become translucent.
Pour in white wine (if using) and stir, scraping up any browned bits, until almost fully absorbed.
Add one cup of hot chicken broth to the rice, stirring constantly until it is almost completely absorbed. Continue adding broth, one cup at a time, allowing each addition to be absorbed before adding the next, for about 18-20 minutes, or until the rice is creamy and al dente.
Stir the cooked chicken back into the risotto.
Remove from heat and stir in the Boursin cheese until melted and fully incorporated, creating a creamy sauce. Season with salt and pepper to taste.
Serve immediately, garnished with fresh parsley if desired.