Hi Novice Baker Dad, we'd recommend using shortening rather than butter. For even better protection against sticking, you might want to try the baking spray we sell, which does a great job! If you happen to be using an older bundt pan that is scratched or worn on the interior, this could also make releasing your cake more challenging. It does help to make sure that the cake is fully baked, as a slightly under baked cake will be more delicate. In addition to the toothpick test, look for the cake to be just starting to pull away from the sides, and a touch on the top of the cake feels firm and leaves no indentation. 

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