• In a medium bowl, whisk together the all purpose flour, whole wheat flour, baking powder, salt and cinnamon. Set aside.
• In a small saucepan, melt the butter over low-medium heat until just fully melted. Remove from heat.
• To the melted butter, add the brown sugar, honey, vanilla and sourdough starter. Mix until fully combined.
• Pour the wet ingredients over the dry ingredients and mix until fully combined.
• Cut the dough into two pieces and shape each into a rough rectangle measuring 1-2 inches thick. Wrap each rectangle of dough in plastic wrap and chill for 30 minutes (or longer. See Note).

When Ready to Bake

• Preheat oven to 325℉.
• Working one piece of dough at a time, place dough on top of a piece of parchment paper. Use a rolling pin to roll the dough into a large rectangle about 1/8 inch thick. 
• Using a pizza cutter or kitchen knife, cut the dough into approximate 2.5 x 5 inch squares but do not separate them.
• Gently score each cracker with a line running horizontally and vertically to look like store-bought graham crackers. Pierce each cracker multiple times with a fork.  
• Transfer the dough and parchment paper to a baking sheet. Sprinkle the top of the cracker dough with cinnamon sugar.
• Bake in preheated oven for 16-18 minutes, rotating the pan halfway through. The edges should be just starting to turn golden brown.
• Allow to cool for 20 minutes, then gently break the crackers into individual crackers at the precut lines.