Place a medium skillet over high heat and melt the butter, being careful not to let it brown. Add the morels and trumpets royales and sauté for a few minutes, or until the mushrooms are wilted.
Add the thyme and the shallots and continue to sauté until the shallots are translucent.
Add the Madeira and reduce until very little moisture is left in the pan. Season with salt and pepper and transfer to a food process. Puree until smooth.
Add the sour cream and season to taste.
Place in a crock and serve..