White Chocolate Blondies

I got this recipe from my friend Brad and they are seriously delicious. I like this recipe a lot better than my other blondie recipe. I made these on Sunday for dessert and the whole family loved them. They're chewy and buttery and the white chocolate is awesome. The original recipe calls for nuts and suggests lining the 9x13 pan with foil and then cooking spray, but I omitted the nuts and just buttered the 9x13 and they turned out beautifully.

1 1/2 cups unbleached all-purpose flour (I just used my regular bleached flour)
1 teaspoon baking powder
1/2 teaspoon salt
1 1/2 sticks (12 tablespoons) melted butter
1 1/2 cups packed light brown sugar
2 large eggs, lightly beaten
4 teaspoons vanilla extract
6 ounces white chocolate chips (1 cup) or chopped bar, or 3 ounces each white chocolate and seminsweet chocolate chips. (I used a whole chopped white chocolate bar plus 1/2 cup semisweet chips)
(1 cup pecans or walnuts--optional)*

1. Adjust oven rack to middle position; heat oven to 350 degrees. Butter 9x13 pan.
2. Whisk flour, baking powder, and salt together in medium bowl; set aside.
3. Whisk melted butter and brown sugar together in medium bowl until combined. Add eggs and vanilla and mix well. Using rubber spatula, fold dry ingredients into egg mixture until just combined; do not overmix. Fold in chocolate (and nuts) and turn batter into prepared pan, smoothing top with rubber spatula.
4. Bake until top is shiny, cracked, and light golden brown, 22 to 25 minutes; do not overbake. Cool on wire rack to room temperature. (Or eat hot like I always do. So yummy.) Cut into squares and serve.

If you want to add the nuts, here's the first step of the recipe:
Spread nuts on large rimmed baking sheet and bake until deep golden brown, 10 to 15 minutes. Transfer nuts to cutting board to cool; chop coarsely and set aside.

If you want to foil-line your pan:
Cut 18-inch length foil and fold lengthise to 8-inch width. Fit foil into length of 9x13 baking pan, pushing it into corners and up sides of pan; allow excess to overhang pan edges. Cut 14-inch lenth foil and fit into width of baking pan in same manner, perpendicular to first sheet. (If using extra-wide foil, fold second sheet lengthwise to 12-inch width.) Spray foil-lined pan with nonstick cooking spray.

(See why I just rubbed butter all over the pan???)