Mix together the flour, salt and baking powder in a bowl. In a separate bowl, cream the butter and sugar with an electric mixer until it becomes light and fluffy. Add the milk to the mixture along with the egg and vanilla, and mix well. Then slowly add the flour mixture until it is just combined.
Shape the dough into a ball, then divide it into two balls. Wrap them in plastic wrap. Place them in the refrigerator to chill for 1 hour.
Lightly dust some flour onto your countertop, and roll the dough out until it is ¼ inch thick. Using a bottle-shaped cookie cutter or stencil, cut out cookies. Place these on a baking sheet lined with parchment paper, cut the centers out 1/3 of the cookies. Bake for about 10 minutes at 350F, until lightly golden. Transfer these to cooling racks and allow to fully cool.
Place the confectioner’s sugar, meringue powder and water into a bowl and beat with an electric mixer for about 7 minutes until the mixture is smooth and when drizzled, stays on the surface for a few seconds. If you find that the icing is too thick, gradually add a few more drops of water.
Divide 1/3 of the icing into 2 bowls and dye the icing green and yellow. Place all 3 colors of icing into piping bags fitted with small, round piping tips.
Pipe a border of white icing around the edges of one solid cookie. Place a cookie with an open center on top and press down to seal the cookies together. Fill the center with pink or blue sprinkles. Pipe white icing around the border of the middle cookie and place another solid cookie on top.
Use the yellow icing to outline and fill in the tip of the bottle. Use the green icing to outline and fill in the top rim of the bottle. Use the white icing to outline and fill in the rest of the bottle. Allow the icing to completely harden to the touch, about 1 hour. Draw the details of the rim of the bottle and measurement markers with the green icing. Allow to harden to the touch, about 30 minutes, then bite into the cookies to reveal the colored sprinkles!
Original article and pictures take https://www.tastemade.com/videos/gender-reveal-cookies site