1Heat oven to 350°F (325°F for dark or nonstick pans). Grease bottoms only of two 8x4-inch or two 9x5-inch loaf pans.
2In large bowl, beat cake ingredients on low speed 30 seconds, then on medium speed 2 minutes, scraping bowl occasionally. Pour into pans.
3Bake 8-inch loaves 37 to 45 minutes, 9-inch loaves 34 to 42 minutes, or until toothpick inserted in center comes out clean. Cool 10 minutes; remove from pans. Cool completely, about 1 hour.
4In microwavable bowl, microwave uncovered on Medium (50%) 15 seconds. Spread frosting over tops of loaves, allowing some to drizzle down sides. Store loosely covered.