For the filling:
Cook all ingredients for 20 minutes; cool; add filling between cake layers.
For the cake:
Grease a 10 x 13 inch round cake pan; lightly flour. In large bowl, combine oil, sugar and eggs; beat at medium speed until light in color. Gradually add flour, beating just until smooth. Gently fold in batter, carrots, nuts and raisins. Pour into cake pan; bake 20 minutes then reduce heat to 115F and bake 50-55 minutes or until toothpick inserted in center comes out clean. Cool 15 minutes. Turn cake out on cardboard; slice into three layers.
In medium bowl, blend all ingredients until well mixed. Spread over top of cake; cut into pieces.
Cajun Country -- New Iberia, Louisiana