In a bowl sift all the dried ingredients ( Flour + Caster Sugar + Salt)
Butter has to be at room temperature (cut butter into cubes), integrate your flour and butter until you a crumbling texture(use a fork), shape it like a ball and let it rest for at least 30 min. Do not knead this dough otherwise your cookies will end too hard.
Before the 30 min pass, set your oven at 350F/180C
After it rested ,roll your dough about 4mm and with cookie cutter shape the dough, bake your Alfajores at 350 F / 180 C for 9 min.
Let them cool for 10 min and then put some“Dulce de Leche” on each side of the cookie and assemble the cookies sandwiches and dust some caster sugar on top.