Let’s break down the process into manageable steps:

Part 1: Making the Cookie Dough

1. 1. Cream Butter, Sugar, and Zest: In the bowl of an electric mixer (stand mixer or hand mixer), add the shortening (or softened butter), sugar, and orange zest. Beat until the mixture is smooth and creamy. This step is crucial for incorporating air and creating a light texture.

1. 1. Add Eggs and Vanilla: Add the eggs one at a time, beating well after each addition. Scrape down the sides of the bowl as needed to ensure everything is well combined. Beat in the vanilla extract.

1. 1. Combine Dry Ingredients: In a separate large bowl, sift together the flour, baking powder, and salt. This ensures that the leavening agents are evenly distributed and removes any lumps from the flour.

1. 1. Alternate Adding Dry Ingredients and Milk: Gradually add the dry ingredients to the wet ingredients, alternating with the milk. Begin and end with the dry ingredients. Mix on low speed until just combined. Do not overmix, as this can develop the gluten in the flour and result in tough cookies.

1. 1. Chill the Dough: Divide the dough in half. Flatten each half into a disc shape. Place each disc in a separate plastic bag (or wrap tightly in plastic wrap). Chill the dough in the refrigerator for at least 2 hours, or preferably overnight. This chilling step is essential for preventing the cookies from spreading too much during baking and for making the dough easier to roll out.

Part 2: Baking the Cookies

1. 1. Preheat Oven and Prepare Baking Sheets: After the dough has chilled, preheat your oven to 375°F (190°C). Line baking sheets with baking mats or parchment paper.

1. 1. Roll Out Dough: On a lightly floured surface, roll out one disc of dough at a time to about 1/3 inch thickness. Keep the other disc of dough refrigerated while you work.

1. 1. Cut Out Cookies: Use your favorite Easter-themed cookie cutters to cut out shapes from the dough. Reroll the scraps of dough and continue cutting out cookies until all the dough is used.

1. 1. Place on Baking Sheets: Place the cut-out cookies on the prepared baking sheets, leaving a little space between them.

1. 1. Bake: Bake for 8 to 10 minutes, or until the cookies are just set and the edges are very lightly golden. You don’t want them to brown much, as this will make them too crisp.

1. 1. Cool: Remove the cookies from the oven and let them cool on the baking sheets for a few minutes before transferring them to a wire rack to cool completely. They must be completely cool before frosting.

Part 3: Making the Frosting

1. 1. Beat Butter: While the cookies are cooling, make the frosting. In a large bowl, using an electric mixer, beat the softened butter until very light and fluffy. This will take several minutes.

1. 1. Gradually Add Powdered Sugar: Gradually add the powdered sugar, beating on low speed until combined.

1. 1. Add Cream: Add the heavy cream and beat on high speed until the frosting is light, fluffy, and holds its shape.

1. 1. Divide and Color (Optional): If you want to use different colors of frosting, divide the frosting into smaller bowls and tint each portion with food coloring. Gel food coloring is recommended for the most vibrant colors without adding too much liquid.

Part 4: Decorating the Cookies

1. 1. Frost Cookies: Once the cookies are completely cool, use a dinner knife or an offset spatula to spread a layer of frosting on each cookie.

1. 1. Decorate: Decorate the frosted cookies with sanding sugar, sprinkles, and other decorations as desired. Get creative and have fun!

1. 1. Let Frosting Set (Optional): If you want the frosting to set more firmly, you can refrigerate the decorated cookies for 15-20 minutes.