Egg is a much harder thing to replace. My son is vegan so my wife is often baking things that are vegan. Chia egg or aquafaba are usually pretty good. She makes a vegan muffin that I honestly prefer to “normal” muffins. Although I’m not 100% sure what she puts in them, I’d bet its applesauce.

Whatever you do, don’t ever have vegan “cheesecake”…. run away… quickly

Pumpkin puree works pretty well too if your recipe can handle a little squashiness.

It serves the same purpose as butter, it's just more common to use butter in baking, don't use oil with a taste (olive oil is to be avoided for example) it will ruin the taste of the cake

and instead of 1 tbsp .... they used 1 cup

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