How do I adjust the cooking time on a baked rice dish if I reduce the recipe by half?
The recipe calls for simmering 30 mins, baking 30 mins, resting 10 mins.


This isn't quite an accurate representation of the recipe. The recipe calls for baking cauliflower and eggplant for 20 minutes each prior to assembly. Once assembled, the rice gets simmered for 30 minutes. Then the completed dish rests for 10 minutes. 

The cook times will likely not be significantly affected by cutting the recipe in half. 


The vegetables are oven roasted in a single layer on baking sheets. Because they are in a single layer, the roasting time will be consistent because the thickness will be consistent. 
Rice generally takes 20-30 minutes to cook through, regardless of the volume. This is due to the time needed for the liquid to fully penetrate and hydrate the rice grains. 


You may want to check both the phases of cooking about 5 minutes prior to the recipe cook times--but I'd likely recommend doing that even if cooking a full recipe.