Preheat the oven to 350 degrees F.
Line an 8-inch square baking pan with parchment, letting ends extend up sides.
In a large bowl, beat butter and brown sugar until crumbly, about 2 minutes.
1/2 cup unsalted butter,, 3/4 cup packed light brown sugar
Beat in egg and wine. Note: The batter may appear curdled.
1 large egg,, 1/4 cup sweet white wine,
In a medium bowl, whisk together the flour, baking powder and salt.
1-1/4 cup all-purpose flour, 1 teaspoon baking powder, 1/4 teaspoon salt
Gradually add the flour mixture to the butter mixture, stirring to mix.
Fold in the baking chips and, if desired, pecans.
1/2 cup white chocolate baking chips, 1/2 cup pecan halves,
Spread the batter into the prepared pan.
Bake until the edges are brown and the center is set (be sure not to over bake!), about 25-30 minutes.
Cool completely in the pan on a wire rack.
While the blondes are cooling, combine the glaze ingredients.
1 cup powdered sugar, 2 Tablespoons sweet white wine,
After the blondies are completely cooled (wait for it!), drizzle the glaze over the blondies.
To remove the blondies from the pan, lifting with the parchment. Then cut into bars. Store in an airtight container.