1. Preheat your oven to 350°F or 180°C.

2. Chop the onion and bell pepper into bite-sized pieces that are easy to cook and eat.

3. In a large pan, cook the chopped bacon over medium heat until it turns crispy and golden brown.

4. Remove the cooked bacon from the pan and set it aside for later use.

5. In the same pan, add the butter and sauté the chopped onion and bell pepper until they become tender and slightly softened.

6. Add the mushrooms to the pan and cook until they release their liquid and start to brown, which should take a few minutes.

7. In a separate bowl, whisk together 250ml or 1 cup of heavy cream, 125ml or half a cup of water, 2 tablespoons of tomato puree, 1 tablespoon of red wine vinegar, 1 teaspoon of paprika powder, 1 teaspoon of soy sauce, and 1 tablespoon of flour.

8. Add the whisked mixture to the pan and stir to combine all the ingredients.

9. Add the cooked bacon, chicken breast fillets, salt, and black pepper to the pan, making sure everything is well coated with the sauce.

10. Bring the mixture to a boil, then cover the pan and transfer it to the preheated oven.

11. Bake for 30 minutes or until the chicken is cooked through and no longer pink.

12. Remove the pan from the oven and stir in the chopped parsley to add some freshness to the dish.

13. Serve hot and enjoy your delicious homemade chicken in creamy sauce.