Niggas is frontin', that's upside-down cake
When baking an upside-down cake, you put stuff on the bottom that you can’t see until it’s turned out.
Hov is using this as a metaphor for “frontin'” because there’s a facade they put up that nobody can see behind until push comes to shove (the cake is revealed).
This can also be wordplay over the “front in”; when you bake the upside down cake, you have to put the front or top of the cake inside the pan.
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