Step 1: Prepare the Dough

1. In a large mixing bowl, cream together the softened butter and granulated sugar with an electric mixer on medium speed until light and fluffy, about 2-3 minutes.
2. Add the egg, vanilla extract, and red food coloring, mixing until fully combined. The dough should have a vibrant red color; add more food coloring if necessary for a brighter hue.
3. In a separate bowl, sift together the flour, cocoa powder, baking soda, and salt.
4. Gradually add the dry ingredients to the wet ingredients, mixing on low speed until just combined. Be careful not to overmix, as this can make the cookies tough.

Step 2: Chill the Dough

1. Cover the dough with plastic wrap and refrigerate for at least 30 minutes. Chilling helps firm up the dough, making it easier to handle and shape.
2. If you’re short on time, place the dough in the freezer for 15 minutes.

Step 3: Make the Cream Cheese Filling

1. While the dough is chilling, prepare the cream cheese filling. In a small bowl, combine the softened cream cheese, powdered sugar, and vanilla extract.
2. Mix until smooth and creamy. Set aside in the refrigerator until ready to use.

Step 4: Shape the Cookies

1. Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.
2. Scoop about 1 tablespoon of dough and roll it into a ball. Repeat with the remaining dough.
3. Roll each dough ball in the red and green sanding sugar, coating it thoroughly for a festive look.

Step 5: Create the Thumbprint Indent

1. Place each sugar-coated dough ball on the prepared baking sheet, spacing them about 2 inches apart.
2. Using your thumb or the back of a spoon, press down in the center of each dough ball to create a small indent.

Step 6: Bake the Cookies

1. Bake the cookies in the preheated oven for 10-12 minutes, or until the edges are set but the centers are still soft.
2. Remove from the oven and allow the cookies to cool on the baking sheet for 5 minutes. If the indent has puffed up during baking, gently press it down again with the back of a spoon.

Step 7: Fill the Thumbprints

1. Once the cookies have cooled slightly, spoon a small amount of cream cheese filling into each indent.
2. If you prefer a neater look, you can pipe the filling using a piping bag or a zip-top bag with a small corner snipped off.

Step 8: Chill and Serve

1. Place the filled cookies in the refrigerator for 15-20 minutes to allow the cream cheese filling to set.
2. Serve the Red Velvet Thumbprint Cookies chilled or at room temperature, and enjoy!

These cookies make a beautiful and delicious addition to any holiday cookie platter, and they’re sure to be a hit with family and friends.