Prepare the Cake:

1. Preheat your oven to 350°F (175°C).
2. In a large bowl, combine all cake ingredients (except raisins and pecans). Beat at low speed until moistened, scraping the bowl often.
3. Once the mixture is moistened, increase to high speed and beat until smooth, scraping the bowl often.
4. Stir in the raisins and 1/2 cup chopped pecans.
5. Pour the batter into a greased 9×13-inch baking pan.
6. Bake for 35–40 minutes, or until a toothpick inserted into the center comes out clean. Let the cake cool completely.

Prepare the Frosting:

1. In a saucepan, melt 1/3 cup butter over medium heat. Cook, stirring constantly, for 4-6 minutes, or until the butter just starts to turn golden brown. Remove from heat and cool completely.
2. In a bowl, combine the browned butter, powdered sugar, and vanilla. Beat at medium speed, gradually adding 2-3 tablespoons of milk until the frosting is smooth and spreadable.
3. Frost the cooled cake with the frosting and sprinkle with 1/4 cup chopped pecans if desired.