Put rice in a casserole dish that has a lid, along with 2-3 cups of water. If you use more water, it’ll take longer to cook but will be much softer. You can speed up the cooking time if you add water that’s already boiling.
Add the rest of the ingredients and the seasonings, changing them for your own tastes, and stir a bit to combine everything.
Put the dish in the oven at 350 degrees F for 1:30 (for 2 cups water) to 2 hours (3 cups water). Make sure the rice and sweet potatoes are soft and fully cooked. Some ovens will take longer than others, and it also depends on the thickness of the dish you’re cooking in. Leave plenty of time – as long as there’s enough liquid, you can’t overcook this dish, the rice will just keep absorbing water and getting larger and softer.
You can easily bake this ahead of time, and then put it back in the oven with a bit more water to reheat and serve.