01 - Preheat your oven to 350°F (175°C). Line a 9x9-inch baking pan with parchment paper, ensuring an overhang for effortless removal.
02 - In a generous mixing bowl, combine the melted butter and packed brown sugar. Whisk until the mixture is smooth and well-integrated.
03 - Add the room-temperature eggs and pure vanilla extract to the wet mixture. Whisk until the ingredients are fully incorporated and the batter appears glossy.
04 - In a separate bowl, whisk together the all-purpose flour, baking powder, and fine sea salt to ensure even distribution.
05 - Gradually introduce the dry ingredients into the wet mixture, folding gently until just combined. Avoid overmixing to maintain a tender crumb.
06 - Delicately fold in the coarsely chopped ginger snap cookies and white chocolate chips or chunks until evenly distributed throughout the batter.
07 - Evenly spread the prepared batter into the lined baking pan, creating a uniform layer.
08 - Dollop spoonfuls of marshmallow fluff or creme over the surface of the batter. Utilize a knife or skewer to artfully swirl the marshmallow into the batter, being careful not to completely incorporate it.
09 - Bake for 28–32 minutes, or until the edges achieve a golden hue and a toothpick inserted into the center emerges with a few moist crumbs – indicating doneness.
10 - Allow the blondies to cool completely within the pan before carefully lifting them out using the parchment overhang. Cut into 16 equal squares.