(makes about 20 sandwich cookies)
Dulce de leche:
- 1 can sweetened condensed milk
- ¼ cup caster sugar
- 3 cups all purpose flour
- 4 tbs chilled unsalted butter, chopped
- 1/8 cup high quality cocoa powder (I love Valhrona)
- 1 egg plus 1 egg yolk
- 1 tbs espresso powder
- 1 tsp baking powder
- ½ tsp salt
- ½ cup plus 2 tbs milk
- Melted high-quality chocolate such as Valhrona, for coating the outside
- To make the dulce de leche, place the unopened can of sweetened condensed milk on a perforated insert inside a large pot (such as a cake cooling rack or a pasta or steamer insert) and cover with water.
- Bring to a simmer, and simmer over medium high heat, for 2 hours, turning the can twice during cooking. Make sure the can is always covered by water.
- Remove can from water and let cool before opening. Be careful when opening it, as the contents will squirt out. If contents are not thick enough, continue to boil until desired consistence is reached (making sure water does not get into can).
- For the cookies, combine ingredients until a ball forms. Shape into a disk, cover with plastic wrap and refrigerate for 2 hours. Roll out to ¼ inch thickness and cut circles out of dough using a 2-3 inch cookie cutter. Bake in a 175ºC (350ºF) oven for 10-12 minutes.
- Cool completely on a wire rack.
- Set cooling rack over a lined half sheet pan. Spoon melted chocolate over cookies.
- Spread chocolate out to an even, thin layer over tops and sides using the back of a spoon (can use the spoon to make a design in the chocolate).
- Refrigerate until chocolate hardens.
- Spread about 1 teaspoon of duce de leche onto cookies.