c("To prepare crust: Preheat oven to 350°.", "Coat bottom of 8-inch square baking pan with cooking spray.", "Place flour and powdered sugar in bowl of food processor.", "Add butter.", "Pulse machine on and off until mixture resembles coarse meal.", "(By hand, place flour and sugar in mixing bowl; add butter.", "Cut butter into dry ingredients using pastry blender or 2 table knives.) Remove mixture from processor; knead gently until dough holds together and forms solid mass.", "Press dough evenly into prepared pan.", 
"Bake on center rack until crust is lightly colored, 15-18 minutes.", "Remove from oven; retain oven temperature. To prepare filling: Beat eggs in mixer on medium speed 1 to 2 minutes.", "Add sugar, flour and baking powder; beat 1 minute at high speed.", "Stir in lime zest and juice. Pour mixture over baked crust and spread evenly with spatula.", "Return pan to oven and bake until top is light brown and center is set, 20-25 minutes.", "Sprinkle pistachios over top, pressing them down so they adhere well.", 
"Let cool completely in pan.", "Using long, heavy, sharp knife, cut into 16 squares.", "If not using immediately, arrange squares on plate and cover with plastic wrap.", "(Bars can be prepared 1 day ahead).", "Serve bars cold or at room temperature.")