Chocolate Banana Pound Cake

From "The Cake Mix Doctor" chocolate book. Be warned--this cake is so rich and moist, you may start letting bananas age just so you can make it!

• Ready In: 48 mins
• Serves: 16

Ingredients

• 2 -3  ripe bananas
• 1 (18 1/4ounce) package  plain  chocolate cake mix (no pudding)
• 3⁄4 cup buttermilk
• 1⁄2 cup  oil
• 3  eggs
• 1  teaspoon vanilla
• 2  cups  peanut butter chips (optional)

Directions

1. Preheat oven to 350. Grease and flour bundt pan.
2. Peel bananas and place in large mixing bowl. Mash completely.
3. Add remaining ingredients. Blend with electric mixer on low speed for 1 minute, scraping sides of bowl frequently.
4. Increase mixer speed to medium and beat 2 minutes more, scraping sides down again if necessary.
5. Pour batter into pan. Bake for 38 to 40 minutes, or until tests done.
6. Remove pan from oven and let sit for 20 minutes. Run sharp knife around edge of cake and invert it onto a rack to cool completely.