3/4 cup (1 1/2 sticks) butter, room temperature
3 tablespoons chopped fresh chives
1 1/2 tablespoons chopped fresh tarragon
1 small garlic clove, pressed
1 (1/2-ounce) package dried porcini mushrooms*
6 1-inch-thick filet mignon steaks
*Available in the produce section of many supermarkets and at specialty foods stores and Italian markets.