Overflowing Bundt Sinks to New Low

I bake a lot. When I bake I sometimes have fails. I recently had a major fail that everyone fell for and didn't even realize I had a fail.
Rainbow Sprinkle Bundt Cake - a chance to use my sprinkles so I can full spent my sprinkle budget for the year... spending a budget is important to be sure not to get a lower budget number for next year... anyway...
Rainbow Sprinkle Bundt Cake was on the menu - the recipe was easy enough - some odd additions to a normal cake mix - but sure OK. The picture on the recipe looked SO good! I loaded up the bundt pan, tossed it in the oven - licked my spatula because it batter was amazing. I set my timer and moved on with my baking adventures for the day. I started to smell something burning. Well... somehow the batter was overflowing the bundt pan - wait - what?! I've never had that happen before - in the history of ever! I scrapped the bottom of the oven and prayed it would bake. The time took MUCH longer to bake - then I pulled it out - it sunk. So not only did it overflow - it was really short - how'd that work out?
I used the toothpick test - all was well. Turned out the cake - let it cool - frosted it with delicious cream cheese frosting - prayed it would look good inside.
The next day at work - I cut the first slice - oh man... the picture in my head and what was in front of me were different cakes. The cake in front of me was almost a tie-dye looking mash-up of colors. Not exactly the white/yellow cake with a scattering of bright color. The cake was super moist - wet almost. The saving grace was it tasted amazing - it just looked like crap. My coworkers didn't know the expectation was a beautiful spotted cake so they were impressed, but me? I was disappointed. Now I want to try it again and see if I messed up. Maybe it'll be better - maybe I'll be cleaning the bottom of my oven again...

Funfetti Bundt Cake
Ingredients
1 white cake mix, dry not prepared
1 small box instant vanilla pudding, dry not prepared
4 eggs
½ cup sour cream
½ cup sugar
¾ cup oil
¾ cup water
½ cup cake sprinkles
Frosting
12 ounces cream cheese, softened
4 cups powdered sugar
1 teaspoon vanilla
Instructions
Preheat oven to 350 degrees F.
Grease and flour a bundt pan and set aside.
In a large mixing bowl, combine cake mix, pudding, eggs, sour cream, sugar, oil, water and beat for three minutes. Stir in the sprinkes
Pour into a bundt pan that has been greased and floured.
Bake at 350 degrees F for 45 to 50 minutes.
Cool in pan on a rack for 7 minutes. Then remove from pan and cool completely.
Cream Cheese Frosting
Combine all ingredients in a mixing bowl and beat on high until smooth. Spoon frosting into a piping bag and pipe the frosting over the top.
Garnish with more sprinkles.