Mayonnaise substitute in cake batter
Many cake batters call for mayonnaise. It makes for moister cakes. Using mayonnaise instead of its constituent ingredients adds convenience as well as extra emulsifiers. It is true that mayonnaise doesn't handle high heat on its own but it doesn't have to. It is part of a batter that will set.

If you really don't trust the recipe- the mayonnaise can be replaced with egg yolks that have oil whipped into them to form an emulsion. You can add a little vinegar for flavor. :)