In a medium-sized bowl, whisk together the flour, salt, and baking powder. Set aside.

In the bowl of a stand mixer fitted with the paddle attachment, cream together the butter and the sugar until the mixture is light and fluffy and creamy. About 2 minutes. Be sure to scrape down the sides of the bowl as you mix.

Add in the egg and vanilla. Continue to mix and scrape down the sides of the bowl to ensure that everything is combining evenly.

Add the dry ingredients to the wet and mix until a nice, soft dough forms and starts to pull away from the sides of the bowl. Scrape down the sides of the bowl, and let the dough mix a few seconds longer to ensure that everything has been combining evenly.

Transfer the dough to parchment paper and flatten it into a disc. Place another piece of parchment paper on top of the dough and roll it rough to about ⅛″ thickness.

Place the rolled out dough on a cookie sheet and transfer to the fridge for at least 2 hours or overnight.

Once the dough has chilled, preheat the oven to 375 degrees F and line two cookie sheets with parchment paper. Set aside

Next, use a 4" potion bottle cookie cutter to cut out as many shapes as you can. I used three different potion bottle shapes by tracing and cutting them out by hand. You can find potion bottle cookie cutters on Amazon to make this step easier.

Use a small 2" circle cookie cutter to cut the center out of each of the potion bottles. Each bottle will need the center taken out.

Place the Jolly Ranchers in a large ziplock bag and use a mallet to crush the candy into very small pieces.

Spoon about 1-2 teaspoons of crushed candy in the center of each cookie. The candy will bubble and spread, so be careful not to overfill the center to avoid the candy from bubbling over.

Bake the cookies for 8-10 minutes or until the edges of the cookies are golden brown.

Allow the cookies to set on the pan for about 10 minutes or until the candy center is hardened, then transfer to a cooling rack. Allow the cookies to cool completely before decorating.

While the cookies cool, you can prepare the royal icing. Mix together the confectioner's sugar and meringue powder with a whisk in a medium-sized bowl. Add the water one tablespoon at a time. A little water goes a long way, so add a few drops at a time and more if needed to reach your desired consistency.

Place a heaping spoonful of icing in a piping bag. This will be used to seal the cookies together later on. Dye the remaining icing whatever colors you want for decorating. Place all of your colors in piping bags and decorate half of the cookies however you want.

Once the cookies have cooled completely, spoon about 1 teaspoon of sprinkles in the center of the undecorated cookies. Use the uncolored icing to pipe icing on top of the perimeter of the cookie to act as a "glue" to seal the cookies together. Place a decorated cookie on top of the "glue" immediately before it dries out. Repeat these steps until all of the cookies are assembled and decorated.