Snap or cut off the woody ends of the asparagus and discard. If the spears are thick, peel the lower parts with a vegetable peeler. Cut off the tips, and cut the remaining stalks into 1/2-inch pieces. Set aside tips and stalks. Cut the mushrooms in half vertically and cut each half into 1/2-inch thick slices. Set aside.

In a large, deep sauté pan, heat 2 tablespoons of the oil over medium-high heat. Add the pancetta or bacon, in two batches if necessary and sauté until browned, 6 to 7 minutes. Remove with a slotted spoon and set aside.

Add the remaining oil to the pan, and then the asparagus and garlic. Sauté over medium-high heat until the asparagus is browned but still firm, about 6 minutes. Remove the asparagus with a slotted spoon and set aside. Add the mushrooms, parsley and red pepper flakes to the pan and sauté over medium-high heat for 4 to 5 minutes, until the mushrooms are browned and beginning to soften.

Return the asparagus and pancetta or bacon to the pan, and stir well to combine the ingredients. Add the brandy and cook for 2 to 3 minutes. Add the broth, tomato sauce and cream and stir well. Bring the liquid to a boil, reduce the heat, and simmer until the mixture reaches a sauce consistency, about 30 minutes.