1. Someone whose behavior can only be described as tarty AND cakey at the same time.
2. An extremely stupid person who says an extremely stupid thing, and leaves you to the point where you are so stunned by this extreme stupidity that the only thing you could possibly make come out of your mouth is tartcake.
3. A very delicious dessert idea, with frosting and sprinkles!
(see definition number 1....if you aren't a tartcake)
Emilee said "Name your children Petey, Treaty, and Smurf." I could only possibly respond with "You, Emilee, are a tartcake."
Then Emilee asked if she had sprinkles, and it verified my above response.