This sauce is ideal over a simple salt-and-pepper steak. Add as many morels as possible.
Heat oil in a large skillet over medium heat. Add shallots and morels and cook, stirring, until tender, about 6 minutes.
Dissolve bouillon cube in water and stir into mushroom mixture. Add milk and sherry and gently simmer until sauce has thickened, about 15 minutes. Season with salt and pepper.