Instructions

Adjust oven rack to middle position and heat oven to 350 degrees. Make parchment paper sling by lining 8-inch square baking pan with 2 long sheets of parchment arranged perpendicular to each other. Push parchment into corners and up sides of pan, smoothing parchment flush to pan. Grease parchment.
Whisk 4 ounces cream cheese, cut into 4 pieces and softened; ¼ cup packed (1¾ ounces) light brown sugar; ¼ cup canned unsweetened pumpkin puree; 1 large egg yolk; ½ teaspoon ground cinnamon; ¼ teaspoon ground ginger; ⅛ teaspoon ground cloves; ⅛ teaspoon ground nutmeg; and ⅛ teaspoon table salt in bowl until smooth; set aside. Combine 1½ cups (7½ ounces) all-purpose flour, ¾ teaspoon baking powder, and remaining ¾ teaspoon salt in separate bowl; set aside.
Melt 12 tablespoons unsalted butter in 10-inch skillet over medium heat. Cook, swirling skillet constantly, until milk solids in butter are color of milk chocolate and have toasty aroma, 3 to 5 minutes. Immediately remove skillet from heat and scrape browned butter into large bowl. Let cool 5 minutes.
Add 1½ teaspoons vanilla, 2 large eggs, and remaining 1¼ cups packed (8¾ ounces) light brown sugar to butter and whisk until smooth. Stir in flour mixture until just combined. Reserve ½ cup blondie batter.
Transfer remaining blondie batter to prepared baking pan and smooth into even layer. Using spoon, dollop cream cheese filling and reserved batter over top, about 6 to 8 dollops each. Drag knife through batter and filling, making swirled pattern, 10 to 12 strokes.
Bake until edges are light golden brown and toothpick inserted in center comes out with few moist crumbs attached, 35 to 40 minutes.
Let cool in pan on wire rack for 1 hour. Using parchment overhang, lift blondies out of pan. Return blondies to wire rack and let cool completely, about 1 hour. Cut into squares and serve.