Raspberry Jam Thumbprint Cookies

0 Blend the dry ingredients together and set aside.
1 Place the butter, sugar and brown sugar in a large mixing bowl.
2 Beat with a mixer until light and fluffy, about 3 minutes.
3 Add the egg and vanilla.
4 Beat until combined.
5 Add the in the dry ingredients.
6 Beat until well blended.
7 Form the dough into a ball and cover with plastic wrap.
8 Refrigerate overnight.
9 Remove the cookie dough from the refrigerator about 10 minutes before you plan to use it.
10 Preheat the oven to 375 degrees.
11 Cover 2 cookie sheets with parchment paper.
12 Roll the dough into 1-inch balls.
13 Roll the balls in Christmas sprinkles if desired.
14 Place the balls of dough 3 inches apart on a cookie sheet.
15 Use a small,rounded measuring spoon or your thumb to make an indentation in the middle of each cookie.
16 Fill each cookie with 1/2 teaspoon of jam.
17 Chill the cookies for 15 minutes.
18 Top with sprinkles if desired.
19 Bake for 10-11 minutes or until light golden brown around the edges.
20 Let sit for 5 minutes, then transfer to a wire rack and cool completely.
21 Dust with powdered sugar, or drizzle with a powdered sugar glaze or melted white chocolate chips.