Step 1: In a small saucepan, simmer the 2 cups of apple cider over medium heat for 20-25 minutes until it has reduced to exactly 1/4 cup of thick syrup. Let it cool completely.
Step 2: Preheat your oven to 350°F (175°C) and line an 8x8 inch baking pan with parchment paper, leaving an overhang on two sides.
Step 3: In a medium skillet, melt the butter over medium heat. Continue cooking, whisking constantly, until the butter turns golden brown and smells nutty. Remove from heat immediately.
Step 4: Transfer the browned butter to a large mixing bowl and whisk in the dark brown sugar and molasses until smooth.
Step 5: Add the egg, vanilla extract, and the cooled apple cider reduction to the butter mixture, whisking until well combined.
Step 6: In a separate bowl, sift together the flour, ginger, cinnamon, cloves, baking powder, and salt.
Step 7: Gradually fold the dry ingredients into the wet ingredients using a spatula until just combined. Do not overmix your apple cider and gingerbread blondies batter.
Step 8: Spread the batter evenly into the prepared baking pan. Bake for 22-25 minutes or until the edges are golden and a toothpick comes out with a few moist crumbs.
Step 9: Allow the apple cider and gingerbread blondies to cool completely in the pan before lifting them out and slicing into squares.