Preheat oven to 325 degrees Fahrenheit.

Cream together the butter and sugar until light and fluffy.

In a small separate bowl, mix the flour and cornstarch until well combined and then add to the butter and sugar. Mix until dough forms. {May take a few minutes. If it seems excessively dry, add another tablespoon of butter.}

Form dough into a ball and wrap in plastic wrap. Place in refrigerator for 20 minutes.

After dough has chilled, roll out onto a lightly floured surface until about 1/4 inch thick. Using a Linzer Cookie Cutter {I bought mine at Michaels, but you can buy them on Amazon as well, if that’s more convenient.} cut out as many cookies as will fit. Be sure to cut out equal sides of back sides and front sides.

Place the dough on a baking sheet and sprinkle with some sugar. Bake for 7-8 minutes. Don’t let them brown around the edges. That will make for hard cookies later on! Let them cool completely on a cooling rack.

Once cooled, place about a teaspoon of dulce de leche in the center of a cookie without a heart in it. Smooth it over, especially in the center, and then top with a heart cookie. Press together ever so slightly and enjoy.