Ingredients

　　6 tablespoons unsalted butter, softened

　　1/4 cup packed light-brown sugar

　　1/4 teaspoon finely grated orange zest (for Rhubarb-Berry Crumbles; optional)

　　1 cup all-purpose flour

　　Pinch of salt

　　Put the butter, brown sugar, and orange zest, if desired, in the bowl of an electric mixer fitted with the paddle attachment. Mix on medium speed until creamy. Stir in the flour and salt. Work the mixture through your fingers until it forms coarse crumbs ranging in size from peas to gumballs.

　　Reprinted with permission from The Martha Stewart Living Cookbook: The New Classics by Martha Stewart Living Magazine, copyright © 2007. Published by Clarkson Potter, a division of The Crown Publishing Group.Buy the full book from Amazon.