Wash hands with soap and water.

Preheat oven to 350°F (175°C). In a large saucepan, bring water to a boil. Add rice, onion, and garlic. Cook for about 30 minutes or until rice is soft.

While rice is cooking, combine milk, condensed cream of mushroom soup, salt, and pepper in a bowl. Mix well. Once rice is cooked, combine rice with the milk mixture, shredded chicken, and chopped broccoli. Mix until well blended.

Grease a 9x13 baking pan and pour the mixture into it. Bake in the preheated oven for 18 minutes. Sprinkle grated cheddar cheese over the top, and bake for an additional 6 minutes or until the cheese is melted.