Step 1

Trim ends of portobello mushrooms. Break stems and caps into small pieces. Finely chop mushrooms in a food processor. Squeeze dry in a clean kitchen towel.

Step 2

Melt unsalted butter in a medium skillet over medium heat. Add shallot; cook, stirring occasionally, until translucent, 2 to 3 minutes. Add mushrooms, and cook, stirring often, until beginning to brown, 5 to 6 minutes.

Step 3

Remove from heat. Stir in heavy cream, dry sherry or Madeira, parsley, and fresh thyme; season with coarse salt and freshly ground pepper. Let cool.