Cook couscous: bring 1 cup water, 2 tablespoons butter and salt to a boil and add couscous. Remove from heat and cover. Leave for 5 minutes.
Heat a large saute pan over medium-high heat. Add 1 tablespoon olive oil and heat.
Season chicken with salt and pepper on both sides
Add the garlic and cook for 1 minute.
Add the chicken and cook about 4 minutes per side, or until cooked through and juices run clear.
Remove the chicken and set aside.
To the same pan, add remaining 2 tablespoons olive oil and add the spinach, mushrooms and bell peppers and cook just until wilted, about 2-3 minutes.
Season with salt & pepper and remove from the pan and set aside.
To the same pan, add the balsamic vinegar, chicken broth and canned tomatoes (feel free to chop up the tomatoes more if you don't want them too chunky) and stir, scraping the bottom of the pan to remove any browned bits.
Bring to a simmer and cook 3 to 5 minutes.
Serve! couscous on bottom, top with the spinach, mushroom & bell pepper mixture, add the chicken and balsamic-tomato sauce on top!
Sprinkle some parmesan cheese if you want & enjoy!