Heat the pan with oil to a smoking point. Add the chicken and let it sear. If the pan is too small the chicken will let out it's juices which is okay too. Wait for the juices to evaporate and let the chicken get some color on both sides. Remove the chicken from the pan.
In the same pan, add a knob of butter followed by diced onions and garlic. Cook till soft and translucent. Add the mushrooms and bell peppers. Cook for about 5 minutes on high. Remove from the pan.
To deglaze, add the wine in the same pan. This step is called deglazing where you extract the bits of charred vegetables and chicken from the pan.This adds depth and flavour. Let the wine come to a boil and reduce in volume to half.
Add the pureed tomatoes. Add the veggies and chicken.
Sprinkle in the herbs, crushed stock cube,paprika and red wine vinegar.
Season with salt. Adjust the acidity/saltiness/heat using vinegar, salt and chilli.
Cover and cook for 20 minutes on low heat.
Garnish with fresh herbs and olives. Serve with rice or bread.