Step 1

Preheat oven to 350° F. Lightly grease a 9x13-inch baking dish.

Step 2

(Skip this step if using leftover cooked chicken or rotisserie chicken.) Cut the chicken breasts into small bite-size pieces. Heat the olive oil in a Dutch oven pot or large skillet over medium-high heat. Add the chopped chicken to the pan and cook until cooked through, then transfer the cooked chicken pieces to a clean plate.

Step 3

Reduce the heat to medium. Add the butter to the pot. Once melted, add the onion and cook, until softened, about 3 minutes, scraping up browned bits from the bottom of the pan. Then add the garlic and thyme and cook, stirring, for 30 seconds.

Step 4

Add the chicken broth, paprika, salt, pepper and uncooked rice to the skillet. Stir and bring to a boil. As soon as it comes to a simmer, place the chopped broccoli on top (do not stir it in). Reduce the heat to a low simmer, cover the pan and cook for 10 minutes without lifting the lid. After 10 minutes, check that all of the liquid has been absorbed by the rice. If not, continue cooking with the lid on until all liquid is absorbed. It's ok if the broccoli and rice aren't quite tender yet, since they will cook more in the oven. Remove pan from the heat.

Step 5

Return the cooked chicken to the pan. Then stir in the milk, grated Parmesan and half of the cheddar cheese.

Step 6

Transfer to the greased baking dish. Top with the remaining cheddar cheese.

Step 7

Cover with foil and bake for 15 minutes, then uncover and bake for 5-10 minutes more until casserole is hot and bubbly.