Preheat oven to 350. Spray a 10-inch cast-iron skillet with cooking spray.
In a large bowl, whisk together melted butter, brown sugar, maple syrup, 2 eggs, and vanilla until combined. In a small bowl, whisk together flour, salt, and baking powder until combined. Stir flour mixture into butter mixture until combined; stir in ½ cup pecans. Spread two-thirds of batter into prepared pan.
In a medium bowl, beat cream cheese, granulated sugar, and remaining egg with a mixer at medium speed until combined, about 1 minute. Spread cream cheese mixture onto batter. Drop remaining batter by spoonfuls onto cream cheese mixture; swirl batters together using a knife. Sprinkle with remaining ¼ cup pecans.
Bake until a wooden pick inserted in center comes out clean, about 50 minutes. Let cool completely on a wire rack. Cut into bars, and drizzle with Maple Caramel Sauce before serving.
MAPLE CARAMEL SAUCE
In a small enamel-coated cast-iron skillet, bring sugar, ¼ cup water, and salt to a boil over medium-low heat. (Do not stir.) Simmer, swirling pan occasionally, until amber colored, 23 to 25 minutes. Remove from heat; gradually stir in cream and maple syrup until smooth. Return skillet to medium-low heat; cook, stirring occasionally, until mixture registers 225° on a candy thermometer, 20 to 25 minutes. Remove from heat; whisk in butter and vanilla until smooth. Let cool to room temperature before using. Refrigerate in an airtight container for up to 1 month.
Recipe by Southern Cast Iron at https://southerncastiron.com/maple-pecan-swirl-blondies/