These are soft shortbread-like cookies filled with sweet and creamy dulce de leche; super simple to make and amazingly good!

Cream butter and sugar on medium speed, until light and fluffy. Add vanilla extract, lemon zest and eggs, and mix.

In a separate bowl, whisk the dry ingredients (corn starch and plain flour). Add to your butter mixture, and mix. Wrap in plastic the cookie dough and refrigerate for 2 hour

Roll dough in a lightly floured surface with a rolling pin, to 6 mm thickness. Cut your cookies with a 2 inch round cookie cutter. Place cookies in your prepared baking sheet.

Bake for 7 minutes, and let cool for a couple of minutes in the cookie sheet. Pipe a bit of dulce de leche filling over your first cookie, then place a second cookie on top, pressing slightly until the Dulce de Leche just reaches the edges. Dust with powdered sugar and enjoy!