Brown Butter Rum Crust

1 3/4 cups finely crushed shortbread cookies
1/2 cup confectioners' sugar
6 tablespoons butter
1 1/2 tablespoons dark rum

Mix crumbs and sugar. Melt butter and heat until very lightly browned. Remove from heat and cool slightly. Stir in rum. Pour over crumb mixture and stir thoroughly. Press over the bottom and sides of a buttered 9-inch pie pan. Chill.