Chocolate Marble Shortbread
Makes ~15 bites, 30 minute prep (including freeze time), 20 minute bake
1/2 cup (8 tbsp) flour
1/4 cup (4 tbsp) butter
1/8 cup (2 tbsp) powdered sugar
1 tsp cocoa powder
1/2 tsp vanilla extract
In a mixing bowl, cream the butter (stir it vigorously until it gets creamy). Add in the sugar, and cream again. Mix in the flour and stir until you are left with a bunch of clumps of flour. Add in the vanilla and stir again - it should now form a ball with the extra moisture. Separate the dough into two equal piles and add the cocoa powder to one. Mix with a spoon a bit, and then finish working the powder in evenly by hand.
Marble the dough as described above and place on a parchment-lined baking sheet. Place, covered, in freezer and preheat oven to 350 degrees. After about 15 minutes in the freezer, remove the dough and indent it with a butter knife along the lines you want it to break. Place it in the oven for ~20 minutes, or a little longer if you want them extra crispy. Let it cool for at least 30 minutes, preferably overnight.