Stained Glass Cookies:
In a bowl, whisk the flour with the baking powder and salt.
In the bowl beat the butter until smooth. Add the sugar and vanilla extract and beat until light and fluffy. Scrape down the sides and bottom of your bowl as needed. Add the egg and beat until combined. Add the flour mixture and beat until you have a smooth dough.

Divide the dough in half and then roll each half between two sheets of parchment or wax paper until it is about 1/8 - 1/4 inch thick. As you roll, periodically check the top and bottom sheets of parchment and smooth out any wrinkles. Place the dough on a baking sheet (along with the parchment paper) and place in the refrigerator until firm (about 30-60 minutes).

Place the cookies on a baking sheet, lined with parchment paper, spacing the cookies about 3 inches (7.5 cm) apart. Then use a smaller Heart ❤️ shaped cookie cutter to cut out the centers of the cookies. (Gather up the scraps and again, roll out the dough, chill, and then cut out the cookies.)
Separate the hard candies by color. Unwrap and place each color of candy Fill the entire cut out of each cookie, (See in pics).

Bake cookies for about 10 minutes (depending on size) or until the edges are just starting to brown and the candy has completely melted. Rotate your baking sheet front to back about halfway through baking. Remove from oven and let the cookies cool completely on the baking sheet before transferring to a wire rack.