First, add 2 tablespoons of butter to a cast-iron skillet on medium-high heat and cook the bell peppers and onions until slightly softened-, about 2 or 3 minutes.
Remove the vegetables and add in the remaining 2 tablespoons of butter. Once melted, add in two tablespoons of flour and garlic. Whisk well until the flour has had a chance to "cook" for about 20 seconds. Then add in the red pepper flakes, oregano, basil, wine, and chicken broth. Reduce the heat to medium and let the mixture simmer for 18-20 minutes.
While the sauce is simmering, cook the pasta one minute less than the instructions say, and do not rinse.
In a second pan, add 2 tablespoons of olive oil and heat to medium-high. Coat the chicken tenderloins in the salt and pepper before tossing in the remaining flour. Drop the chicken into the pan and cook for 3 to 4 minutes on each side. Remove the chicken from the heat.
When the sauce is reduced by half, add in the heavy cream and whisk well until you have a nice thick sauce. Add in the lemon juice and half of the parmesan cheese and whisk.
Spoon the pasta into a serving bowl, add the creamy sauce, and add a spoonful of the bell peppers. Top it with the chicken and serve hot.