As brown rice takes a long time to cook on the stove top it is worth cooking for free, using zero emissions in the solar oven. The water is contained in the casserole and so changes the rice to water cooking ratio to 1:1
1 cup brown rice
1 cup of water
Put rice and water in a small casserole, put the lid on, and place in the oriented oven.
Remove when the water is absorbed and the grains are soft.