In a large bowl, cream the butter and sugar until light and fluffy. Beat in the eggs and vanilla.

In another bowl, stir together the flour, cocoa, baking powder and salt.

Gradually add the dry ingredients into the wet ingredients.

Shape the dough into a disc and cover with plastic wrap. Refrigerate 30 minutes or longer until firm. You could also freeze the logs at this point in the recipe to bake later. Wrap in aluminum foil after the plastic wrap if you want to freeze cookie dough.

Preheat oven to 350°F.

On a surface dusted with cocoa powder or flour, roll out the dough and cut out heart shapes.

Place the cookies on baking trays lined with parchment paper. Place the baking trays in the refrigerator to chill the cookies for another 30 minutes before baking.

Bake cookies for 8 to 10 minutes or until edges of slices are golden.

Remove cookies from baking sheets, and place on wire racks. Let cool completely before dipping in the melted white chocolate.

Melt the white chocolate according to the package directions.

Make sure the cookies have cooled completely before dipping half the cookie into melted chocolate.

Dip the melted chocolate cookie side immediately into the sprinkles.

Place the cookies on a piece of wax paper to completely harden before storing in plastic containers.