Prep the chicken: Pat the chicken dry and cut into small, even pieces.
Sprinkle with 1/2 teaspoon salt, pepper (if using), garlic powder, and onion powder. Toss to coat.
Heat the pan: In a large, deep skillet or Dutch oven, warm the butter and olive oil over medium heat until the butter melts and starts to foam.
Brown the chicken: Add the chicken in a single layer. Cook for 5–7 minutes, stirring occasionally, until the edges are golden and the centers are just cooked through.
Transfer the chicken to a plate and set aside.
Toast the rice: Add the uncooked rice to the same pan. Stir for 1–2 minutes to coat the grains in the remaining fat. This helps the rice stay fluffy and adds a subtle nutty flavor.
Simmer the rice: Pour in the chicken broth and the remaining 1/2 teaspoon salt.
Bring to a gentle boil, then reduce heat to low. Cover and cook for 12–15 minutes, or until most of the liquid is absorbed and the rice is tender.
Make it creamy: In a small bowl, whisk the milk and cream. If you prefer a thicker sauce, whisk in the cornstarch until smooth.
Stir this mixture into the cooked rice.
Add cheese: Reduce heat to low. Add the cheddar and mozzarella, a handful at a time, stirring until melted and smooth. If the mixture seems too thick, add a splash more milk.
If it’s too loose, let it simmer gently for a few minutes to thicken.
Finish with chicken and veggies: Return the cooked chicken to the pan and stir to combine. Fold in peas or your child’s preferred veggie. Warm through for 2–3 minutes, stirring gently.
Taste and adjust: Season with a pinch more salt if needed.
For kids who like a hint of brightness, add a tiny squeeze of lemon or a small pat of butter for extra richness.
Serve: Spoon into bowls. For very picky eaters, you can top with a little extra melted cheese or keep veggies on the side so they can mix at the table.