I learned how to make this card at a Jubilant Butterflies meeting a while ago. It looks pretty basic, but there is a hidden flap that you pull out to the left that reveals a hidden message.
You might wonder what stamp I used to get the scalloped oval underneath the banner on the front of the card. I used one of the stamps in the Everything Eleanor stampset, which could have been cut out using a Framelit from the Apothecary Accents set. But, instead of the framelit I used the scalloped oval punch and covered the original saying with the banner. You can do most anything you want with any stamp, just try!