Preheat oven to 425 degrees F.
Line a large baking sheet (18” x 13”) with parchment paper and lightly spray parchment with non-stick cooking spray. Set aside for now.
In a medium bowl, whisk together flour, brown sugar, baking powder, cinnamon, ginger, nutmeg, baking soda, salt, and ground cloves. Set aside.
In a large bowl, whisk together buttermilk, molasses, butter, eggs and vanilla extract. It is important that all of the wet ingredients are about the same temperature (room temperature) before mixing them together. If the buttermilk is too cold, it will clump the melted butter together. If the melted butter is too hot, it will start to bake the eggs.
Pour the dry ingredients into the wet ingredients and whisk until combined. Do not overmix – a few small lumps are okay. Do not use an electric mixer for this or the batter will be overmixed.
Pour the batter evenly onto the prepared baking sheet. Use a spatula to evenly spread the batter over the baking sheet.
Bake in the oven for 15 to 17 minutes or until a toothpick inserted in the middle comes out clean.
Let cool in pan (on wire rack) for 15 minutes before slicing and serving.