Preparation Steps

• Preheat the oven to 350°F (175°C). Line two baking sheets with parchment paper or silicone baking mats and set aside.
• In a medium bowl whisk together the flour, cocoa powder, baking soda and salt until evenly combined. Set the dry mix aside.
• In a large mixing bowl, beat the softened butter and granulated sugar with an electric mixer on medium-high until very light and fluffy, about 3 minutes. Scrape the bowl down as needed.
• Add the egg, vanilla, apple cider vinegar and red food coloring to the creamed butter and mix on medium speed until the color is uniform and the mixture is smooth.
• Fold the dry ingredients into the wet mixture with a spatula or mix on low just until no streaks of flour remain. Avoid overmixing to keep cookies tender.
• Chill the dough in the refrigerator for 15 minutes — this firms the dough for neater shaping and a slightly thicker cookie.
• Roll dough into 1-inch balls (about 1 tablespoon each) and place them 1 1/2 inches apart on the prepared sheets. Use the back of a teaspoon or your thumb to press a shallow well into the center of each ball, about halfway through but not to the bottom.
• Bake one sheet at a time on the middle rack until the edges are set and the centers look just slightly soft, 9–11 minutes. Rotate the pan halfway through if your oven runs hot.
• Remove the cookies from the oven and immediately press a white chocolate wafer into the indentation of each cookie. Let the cookies cool on the baking sheet for 4–5 minutes so the wafers soften and adhere, then transfer them to a wire rack to finish cooling.
• If any wafers don’t melt smooth into the centers, microwave a few extra wafers in 10-second bursts until soft and spoon a small amount into the wells to finish.
• Cool completely before storing. Cookies keep in an airtight container at room temperature for up to 4 days or freeze for longer storage.