Add 2 tbsp of olive oil in a large-pot and heat on medium-heat. For color and texture, slice the sausage and sear it on both sides. Put aside the sausage from the pan.
Melt 2 tbsp butter to the onions and add the diced onions. Cook for 5 minutes or till the onions are softened. Add the garlic and cook for few minute.
To the pan, add 1 tbsp olive oil and the chicken broth. To give the dish more flavor, run a silicone spatula across the bottom of your pot to remove any brown remanence from the sausage.
Add the rice. and bring to a boil and reduce to a simmer. Cover tightly and cook for 10 minutes.
Add the bell peppers seal the lid and don't stir. This will cause the rice to become stickier and release starch and cook for 5-10 minutes more.
Turn off the heat. Cover it. Let it rest for 10 minutes. During this time, any rice that remains on the bottom of the pot will be released.
Reduce to low-heat. Mix in the cream of chicken soup, cheese, milk and sour cream. Mix well. Add in the sausage and red pepper flakes. Stir and cook until heated through. Turn off the heat and serve.