Definition: In this task, you have to generate the title of the recipe given its required ingredients and directions.
Input: ingredients:  'Filling', '2 tablespoons lemon zest, finely grated', '1/4 teaspoon salt', '1/2 teaspoon vanilla', '3/4 cup unsalted butter (1 1/2 sticks softened to room temp)', '3 cups powdered sugar', 'Cookies', '1/2 cup lemon juice, fresh squeezed', '1 tablespoon lemon zest, finely grated', '3 3/4 cups all-purpose flour', '1 teaspoon salt', '1/2 teaspoon baking soda', '1 cup unsalted butter (2 sticks softened room temp)', '1 1/2 cups sugar', '2 large eggs', '2 large egg yolks',<sep> directions: 'Filling:', 'Using the back of a spoon mash lemon zest and salt to a paste in a medium bowl.', 'Add butter. Using an electric mixer, beat until fluffy.', 'Add powdered sugar in 4 batches, beating after each addition until well blended.', 'Cookies:', 'Boil lemon juice and lemon zest in small pan until the mixture is reduced to two tablespoons, this takes about four minutes, watch it closely.', 'Pour into a small bowl and let cool.', 'Sift flour, salt, and baking soda into a small bowl.', 'Using an electric mixer beat butter in a large bowl until fluffy.', 'Add sugar, beat until well blended.', 'Beat in two whole eggs, one at a time, then beat in two egg yolks.', 'Beat in lemon juice mixture.', 'Add in dry ingredients and stir until well blended but do not overstir!', 'Cover dough and chill until very firm, at least four hours and up to one day.', 'Preheat oven to 375°F Line 2 baking sheets with parchment paper.', 'Roll out dough on lightly floured surface to scant 3/8 inch thickness.', 'Using 2 inch round cookie cutter, cut out cookies.', 'Transfer cookies to baking sheets and bake one pan at a time for best results.', 'Bake for 12 minutes or until edges are golden brown.', 'Transfer to racks and cool completely, repeat with remaining dough.', 'Spread 2 tablespoons of filling on the flat side of one cookie. Top with another cookie.', 'Repeat process to make your sandwich cookies.', 'Can be made 2 days ahead.', 'Store airtight in the refrigerator.'

Lemon-Cream Sandwich Cookies