Beat on low speed until moistened. Beat for 2 minutes at medium speed.
Stir in nuts and raisins. Pour into greased pan.
Bake for 25-30 minutes or until toothpick comes out clean. Bake for 40-50 minutes if placed in a 9x13" pan. Cool completely.
In a small bowl, combine all the frosting ingredients. Beat until smooth.
Frost cooled cake. Store in the refrigerator.