Add the buttermilk and sugar, then whisk until well combined. Add the eggs and whisk again.
Add flour and whisk until smooth and lump free. It will seem lumpy at first, but keep stirring. It will get nice and smooth. Fold in the sprinkles.
While the cake is cooling, make the icing. Place the butter in a medium-large microwave-safe bowl. Microwave on high power for 1 minute or until the butter is melted.
See Café Tips above in the post for more detailed instructions and tips to ensure success.
Be sure to read the section above in the post on "What type of sprinkles I should use for this Funfetti Cake?" before making this recipe.
If you prefer to use Metric measurements there is a button in each of our recipes, right above the word “Instructions”. Just click that button to toggle to grams, milliliters, etc. If you ever come across one of our recipes that doesn’t have the Metric conversion (some of the older recipes may not), feel free to leave a comment and I will add it.