Mini Homemade Pop Tarts

1 . Stage

Combine fruit filling ingredients and 3 tablespoons water in a medium pot over medium heat; stir. Gently mash berries with the back of a wooden spoon and simmer, stirring frequently, for 30 to 40 minutes, or until filling has thickened. Let cool.

2 . Stage

Cut chilled dough into 4 equal pieces. Roll 2 pieces into equal rectangles about 3- by- 8 inches. Fill a piping bag with Nutella and a second piping bag with marshmallow crème. Onto one of the rectangles, pipe rows of Nutella 1/2 inch apart. Pipe rows of marshmallow crème on top.

3 . Stage

To make the egg wash, whisk together egg and heavy cream. Using a pastry brush, carefully brush egg wash onto dough between the rows of filling. Gently lay the second dough rectangle over top and press around each mound of filling. (Tip: This is the same method used for homemade ravioli.) Cut 1- by- 1 1/2-inch rectangles with a pizza cutter (you should have 12 tarts) and press the back of a fork along the edges to seal. Place tarts on one of the prepared sheets and brush lightly with cream. Cut 3 tiny slits in the top of each tart. Bake for 12 to 15 minutes, or until golden brown. Place on wire racks to cool completely. Repeat the process with the remaining two slabs of dough and the cooled fruit filling to make 12 fruit-filled tarts.

4 . Stage

For the icing, in a medium mixing bowl or the bowl of a stand mixer, beat egg white on medium-high speed for 2 minutes, or until light and frothy. Add powdered sugar, 1/4 cup at a time, until mixture is thick and smooth. Add vanilla and beat for 1 minute more. Spread icing onto pastries with an offset spatula or your fingers. Top with sprinkles.

5 . Stage

For the pie dough, in a medium mixing bowl, sift together flour, baking powder, and salt. Add butter and cream cheese and cut into dry ingredients with a pastry knife or your fingers until fine crumbles are formed. Add buttermilk and, using your hands, gently work mixture until dough just comes together. Form dough into a disk, wrap with plastic wrap, and refrigerate until ready to use.