In a large sauté pan, heat the butter and olive oil over medium heat. To the pan, add the garlic, onion, and shallot. Sauté until the onions are soft and translucent and the garlic is fragrant. About 5 minutes.
To the pan, add the mushrooms and 1 cup chicken stock. Sauté until mushrooms are soft and have released their liquid. About 5 minutes.
Add the cauliflower and remaining 1 cup of chicken stock and stirring frequently, sauté for 10 minutes.
Reduce the heat to low, stir in the heavy cream, Parmesan cheese, parsley, salt and pepper. Let simmer for 10 to 15 minutes to thicken.