I don't blame you for being confused!
I have never heard this phrase- where did you find it? Please give us some context when you post as it helps us to help you, and is in fact a forum requirement.
Luckily we don't eat pizza - this phrase would put me off for life. Talk about mind boggling imagery.
(The Domino's did a promotion campaign to save its bad reputation because of the bad taste of old pizza,and launched a new pizza.)
Below is the context:
"Now Domino's has a new pizza and they say the only thing that's the same...
It's still round.
All that stuff about their old pizza tasting like cardboard...
I mean that hits you right in the heart.
...which prompted one critic to post: "What kills me is why does the guy who is the head chef in the Domino's commercial still have a job?"
Stephen Colbert reviewed the new pizza...
Is that pizza or did an angel just give birth in my mouth?
...while noting the honesty of the ad campaign." Domino's old pizza's cheese did not taste good， had no aroma， was not cheese.
Actually I don't see any clue in the context to help me understand the phrase...
Stephen Colbert is a comedian. He frequently says things that intentionally sound very odd because that is part of his humorous style. A normal person would not have said that as it sounds disgusting and ridiculous (angel's don't have babies). He is making exaggerated fun of the ways in which people rave about things in commercials and advertising.