Chocolate Strawberry Hearts | Seasoned Cooking

Preheat oven to 375°F. Line cookie sheets with parchment paper; set aside.
In a large bowl, stir together cookie mix, cocoa powder, butter, and egg until dough comes together. Shape mixture into a ball and wrap in plastic wrap. Chill in refrigerator for at least 30 minutes.
On a lightly floured surface, roll out dough to 1/4-inch thickness. Using a 2 1/2-inch heart-shape cookie cuter, cut out shapes. Reroll dough scraps and cut out more cookies until all the dough is used. Space half the cookies 2 inches apart on prepared cookie sheets. Bake for 7 to 9 minutes or until edges are firm and bottoms are light brown. Cool on cookie sheets on a wire rack for 5 minutes. Transfer cookies to wire rack; cool completely.
Using a 1 1/4-inch heart-shape cookie cutter, cut out the centers of the remaining cookies. Space cut-out hearts 2 inches apart on prepared cookie sheets. Arrange the heart centers on another prepared cookie sheet. Sprinkle with sparkling sugar. Bake for 6 to 8 minutes or until edges are firm and bottoms are light brown. Cool on cookie sheets on a wire rack for 5 minutes. Transfer cookies to a wire rack; cool completely.
Spoon about 1 teaspoon of the strawberry jam on each of the whole cookies. Top with cut-out cookies. Spread half the cut-out heart centers with some of the remaining jam; top with remaining cut-out heart centers to make tiny heart cookie sandwiches.