well, let's take a look at two independent events
A) the potato is hot
B) it's raining
now, the potato could be hot whether is raining or not, A is totally independent of B, so what's the probability of "the potato being hot, GIVEN that it's raining" P(A | B) is the same as if it wasn't raining, or P(A), the fact that B occurred, doesn't affect A at all, the potato is hot regardless, rain or not. So P(A | B) = P(A).