Regular lines are sung by Tiana, lines in italics by Naveen. The final verse has both singing at the same time.

What is this? What is this?
I've turned to a frog after just one kiss.
Foolish risk. Foolish risk.
I'll always be a waitress.

What is this? What is this?
The curse should be gone after just one kiss.
How'd I miss? How'd I miss?
What do you mean you're not a princess?!

What is this? What is this?
Now how will you keep your promise?
You did this! I did this?
It's your fault I'm now in this mess.

What is this? What is this?
Then what were you doing wearing that dress?
You did this! I did this?
It's your fault I'm still in this mess.

[Both] What is this? What is this?
I've turned to a frog after just one kiss / The curse should be gone after just one kiss
[Both] You did this. You did this!
[Both] It's your fault I'm now in this mess.

*croak*