Warm the pot. In a large, heavy pot or deep skillet with a lid, heat the olive oil over medium heat.
Soften the aromatics. Add onion and carrot.
Cook 3–4 minutes, stirring occasionally, until slightly softened. Add zucchini and cook 2 more minutes. If using garlic, stir it in for 30 seconds.
Toast the rice. Stir in the rinsed rice and let it toast for 1–2 minutes.
This helps the grains stay fluffy and adds a nutty note.
Season and add chicken. Add the chicken pieces, salt, pepper (if using), thyme, and paprika. Stir to coat everything evenly.
Pour in the broth. Add the broth and bring to a gentle boil. Give the bottom of the pot a good scrape to release any bits.
Cover and simmer. Reduce heat to low, cover tightly, and simmer for 15 minutes.
Avoid lifting the lid—steam is doing the work.
Add peas. Sprinkle in the frozen peas, quickly stir, and cover again. Cook 5–7 more minutes, until rice is tender and chicken is fully cooked.
Rest and finish. Turn off the heat and let the pot sit, covered, for 5 minutes. Fluff with a fork.
Stir in lemon juice and parsley if you like.
Adjust for toddlers. For very young eaters, mash a portion lightly with a fork or add a splash of warm water or broth to soften further.
Serve warm. Taste and add a pinch more salt for adults, or finish with extra herbs or grated Parmesan at the table.