Preheat a large ovenproof skillet to medium-high heat, and preheat the oven to 400F. Add the pine nuts to the skillet and toast just until fragrant, for about 3 minutes. Turn the skillet off.
Add the rice, stock, mushrooms, and garlic to the skillet. Stir to combine, and sprinkle lightly with salt, especially if you're using homemade or unsalted stock.
Sprinkle the chicken and the broccoli over the rice mixture.
Combine the cheese, sour cream, and cream to form a thick sauce. Drizzle or drop spoonfuls of the sauce over the broccoli - the sauce may not cover the whole skillet, that's ok!
Bake the dish for 30-45 minutes until the liquids are absorbed and the rice is tender. If the dish starts to brown on top before the rice is cooked, tent lightly with foil to finish cooking.
Serve. Eat. Enjoy!