Beat soft butter with sugar and oil, with a whisk or a hand mixer
Add eggs, flavorings and mix well
Sift cocoa powder making sure it's well integrated
Add sifted dry ingredients in 2 parts, beating only until it's integrated
Finish with a spatula to prevent overbeating; cover and refrigerate
Scoop portions of chilled dough, place on parchment-lined cookie sheets and bake
Beautifully plump and crackled
Fill with thick cream cheese mixture and sandwich together
Or try them filled with Dulce de Leche