Preheat your oven to 375°F.
Cut you squash in half, remove seeds and strings with a spoon and brush the insides generously with olive oil. Bake face down in a baking dish for 45 minutes - 1 hour.
Meanwhile, cover and pound chicken breasts with a meat tenderizer. Then sprinkle with salt and pepper.
Heat oil in a large skillet. Add the chicken and brown about 3 minutes on each side. Turn off the flame. Remove chicken to a plate, cover and set aside.
Then add the diced tomatoes to the oil in the skillet, bring to a boil and simmer about 30 minutes. The tomatoes will break down as they simmer. Stir occasionally, crushing the tomatoes with a fork.
Add garlic and butter and stir.
Add the chicken back in stir and heat through. Finally, stir in the basil and olives.
By now your squash should be done and cool enough to handle. Scrape the spaghetti like strands from your squash and divide onto individual plates. Top with chicken and sauce.