Heat the olive oil in a medium-sized saute pan over medium heat and add the sliced mushrooms. Saute for about 5 minutes, until the mushrooms begin to soften. Meanwhile, bring a large pot of water to boil.
Add the seasonings, including the garlic powder, oregano, thyme, salt and black pepper to the mushrooms and stir to coat the mushrooms in the spices. Saute another two minutes.
Push the mushrooms to the outside of the pan and add the butter to the middle of the pan, and melt. Once the butter is melted, add the flour to the pan, while stirring quickly. Coat the mushrooms in the flour and butter 'paste' and continue stirring until there are no lumps or white flecks of flour left, about one minute.
Your water should be boiling by now, add your pasta and a palmful of salt to the water and boil for five minutes while you finish up with the sauce.
Add the chicken stock to the pan and stir to combine. Turn the heat down to medium-low and simmer for 5 mins.
Add the cream to the sauce, and stir to combine. Simmer briefly, about 30 seconds.
Add the cheese to the sauce and stir to melt completely. Turn the heat off and add your cooked pasta directly into the sauce. Stir to coat the pasta in the sauce and serve immediately.