Almost every time I make rice, I make it for just me and my partner. We've found that the right amount for us is 1/2 a cup (125mL, a regular cup not a rice cooker cup) of uncooked basmati rice. I make it in the microwave, with 1 cup of cold water, uncovered, 10 min on high and 5 min rest, but it's never as good as when I make a whole cup. I've tried varying the cook and rest times, but it only seems to get worse (dryer).  What other ways could I cook such a small amount of rice? 
After much experimentation my partner found the answer:   ½ cup basmati rice 1¼ cup water 10 minutes on high   The extra 25% water means the rice is cooked through perfectly. I assume with such small quantities the steam vented out of the microwave is more critical and so extra water is needed. 