My preferred version:
Two sausages are sitting in a frying pan. One looks over to the other and says, "Is it just me, or is it getting hot in here?" The other sausage looks back and says, "AHHH! IT'S A TALKING SAUSAGE!"
Given the lack of punctuation at the end of the sentence compared to proper punctuation on the other lines, I would expect that one of these is true:
There is text on the right (starting with Wh) which might be part of the joke or a different one or they might be separated but connected somehow. We will never know
Why does the muffin scream? Just look around. Why shouldn't the muffin scream? Why aren't you screaming?
It's an anti-joke. Instead of doing a typical setup-payoff, the setup is that it uses the format of a joke, but then subverts the expectation by then having the "characters" make the most basic observations/actions.
I think it's implied that the other muffin screams cause it's surprised by a talking muffin.
The full joke adds that the other muffin says "a talking muffin" after the scream,but I kinda like this version better because it's an antijoke this way.