Heat olive oil in your largest Dutch oven or heavy-bottomed pot over medium-high heat. Season chicken pieces generously with salt and pepper, then sear them for 4-5 minutes per side until golden brown. Remove chicken to a clean plate and set aside temporarily.
Add diced onion and sliced carrots to the pot, stirring frequently for 3-4 minutes until softened and fragrant. The one pot chicken rice method starts with building flavor through proper vegetable searing. Add minced garlic and celery, cooking an additional minute until the mixture becomes aromatic.
Pour in 2 cups of long grain white rice, stirring constantly for 2 minutes to toast the grains lightly and seal in their starches. This creates a subtle nutty undertone that elevates the entire dish. Add chicken broth, bay leaf, thyme, and rosemary, stirring well.
Return chicken pieces to the pot, nestling them among the rice and vegetables. Bring to a boil over high heat for 2 minutes, then immediately reduce to low heat and cover tightly with a lid. Simmer undisturbed for 25-30 minutes until rice absorbs the liquid and chicken reaches 165°F internally.
Remove from heat and let rest covered for 5 minutes to allow complete moisture absorption. Stir in frozen peas and fresh parsley, fluffing gently with a fork. Taste and adjust seasoning as needed before serving.