In a food processor, pulse the flour, powdered sugar, and salt together. Add in the butter cubes and pulse 7 times. Add in the cream and egg yolks and mix on low until a crumbly dough appears. Turn out onto a clean work surface and kneed into a disk. Wrap in plastic wrap and place in the fridge to chill for 1 hour.

For the filling, Add the raspberries, sugar, and lemon juice into a medium saucepan over medium heat. Cook for about 5 minutes until warm and simmering. Mix the corn starch and water to make a slurry. Add to the raspberry sauce and mix continuously until bubbly and thickened. Set aside to cool.

Preheat the oven to 400 degrees.

Roll out the dough into 1/8th inch. With a heart shaped cookie cutter, cut out the shapes and place on a lined baking sheet 1 inch apart. Gather the dough pieces and roll out again to make more heat shapes.

To assemble, fill one hearts with about 2 tablespoons of raspberry filling. With the egg wash, line the edges, top with another heart and press against the edges to assemble. Using a fork, press in a few dimples. Brush the tops with egg wash.

Place in the preheated oven for 15-18 minutes until just golden.

In a standing mixer, whisk the powdered sugar and egg white together until it holds its shape when drizzling on itself but will eventually melt in, about 5 minutes.

Once cooled, drizzle the hearts with frosting and top with sprinkles. Let set overnight to harden.