Here is what I do for lunches. It may not be for everyone, but I love the convenience and not having to cook something up all the time when my mind is elsewhere during the day.
I cook up a pot of whole grain brown rice (i use chicken broth instead of water for a better flavor). I keep the whole thing in a storage container in the fridge and toss a plastic one cup measure in with it.
I also bake chicken breasts in the oven - a whole cookie sheet full at a time. I buy the frozen ones in a bag. Defrost them in the microwave and cut them in half to make 3-4 oz. portions. I line my cookie sheet with foil, and sprinkle it with spices (I like the Red Robin restaurant spice which you can buy at the restaurant, I also like lemon pepper spice, Misty's BBQ seasoning, pretty much whatever you like!). Then I lay the chicken pieces on and spice the tops as well. I usually make 2-3 differently spiced kinds at a time. I bake mine in the oven at 400 degrees for about 25 minutes or so - whenever the juices run clear. When these are cool I toss them in a ziploc and keep them in the fridge.
So for lunches I can do:
*Lettuce salad topped with chicken & whatever other veggies I have around
*Put a teensy bit of extra virgin olive oil in a pan and stir fry a cup of rice with some of the chicken cut into strips
*Heat a serving of the rice as a side to some of the chicken or other lean meat
*Make chicken salad with chopped cucumbers & light Miracle Whip (if I am feeling daring (lol) I cut up seedless red grapes in it too - it is delish!).. and put on a piece of whole grain bread
*Toss some EVOO in the pan and stir fry some fresh veggies a bit, then add a cup of brown rice for another nice stir fry
... you get the idea. Chicken isn't the only thing I eat - but it is most of what I eat because it is such a lean protein. Brown rice fills me up for quite some time - especially combined with a lean protein.
I have other lunches I make as well, but I think this is my best tip because it is fast, convenient (after just a bit of initial prep) and tasty! Having those two things in the fridge has saved me many times from just grabbing whatever is around.
BTW.. 1 cup of prepared brown rice is about 200 calories. Each ounce of boneless, skinless chicken breast is about 30 calories.
Hope that might help you some!