In a mixing bowl, add ½ cup butter and 1 cup brown sugar. Beat until it begins to get creamy. Stop mixing. Add in 1 tsp vanilla, 1 tsp baking powder, ½ tsp salt, and mix together just until it is combined. Add in 1 cup all-purpose flour, 2 cups whole wheat flour, and ½ cup milk. Mix well after all ingredients have been added. Your dough will be very thick.
Roll your dough into a ball and then slightly flatten it out. Wrap in plastic wrap and place in the refrigerator for at least four hours or overnight.
Preheat your oven to 350F and then pull the dough out of the fridge. Roll dough out on a lightly floured surface until it is about 1/8 inch thick.
Cut with a pizza cutter into squares or rectangles. Place squares onto a parchment paper-lined cookie sheet. Use a fork to create indents and sprinkle the top of all crackers with granulated sugar.
Bake for 8 to 12 minutes or until the edges begin to turn gold. Allow for cooling to room temperature.