One of my easiest ways to make a meal is to add some veggies to a boxed pasta/rice thing. I don't know how common things like that are in Japan (obviously the flavors would be more regionalized if they were), but I'm talking Pastaroni type stuff. Just get the mix going according to its instructions, sautee up whatever veggies you like (and meat, in your case), then stir them together and you have a full meal that you didn't even need to season.