• Add flour, sugar, salt, baking powder, and baking soda to a food processor. Pulsa a few times to combine.
• Add cold cubed butter and shortening and pulse until crumbly. Use a spatula to scrape the sides of the bowl.
• Whisk egg, milk, and lemon extract in a small bowl and drizzle over the other ingredients in the food processor. Pulse until the dough comes together. Dump the mixture out of the food processor and onto plastic wrap and roll into a log.
• Divide the dough into 3 equal portions. Leave one portion out and refrigerate the rest. Flour your work surface and rolling pin. Roll the dough out to about ⅛" to ¼" thickness. Use a heart-shaped cookie cutter to cut out the cookies.
• Use a pastry scraper to transfer the cookies to a parchment-lined cookie sheet. Leave enough room for the cookies to expand. Bake in a preheated 350-degree F oven for approximately 6-8 minutes or until lightly browned around the edges. 
• Allow cookies to cool on the baking sheet for a few minutes then transfer them to a wire cooling rack. Continue this process until all the cookies are baked.

How to Decorate the Cookies

• Place white chocolate chips in a small ziplock bag. Work the chips into the corner of the bag and twist, secure with a rubber band. Place the chocolate chips in a small bowl. Pour hot water into the bowl. You may need to massage the bag for a minute until the chocolate is completely melted.
• Cut the tip of the bag to allow the chocolate to be squeezed out, then gently squeeze the melted chocolate out of the bag to decorate the cookies. Before the chocolate hardens, top the cookies with sprinkles.

Glaze (optional)

• Whisk sugar, milk, and extract in a bowl until smooth. Add more milk or sugar until you reach the desired consistency. Divide the icing into smaller bowls and add food coloring to make different colored icing. Use to decorate cooled cookies.