I found a free pattern for this Ruffled Halter by oliver + s It was very time consuming to do - first off the pattern prints out on 24 sheets of paper and you have to tape them all together perfectly . . . after that, everything else seemed like a breeze.
But I spent one day assembling the pattern, another cutting out the pieces in the fabric, and a 3rd sewing it all together. I think it would have been way too much to try and get it all done in one day. The instructions were easy for me to follow and I didn't even have to unpick anything and start over! I love it in the red gingham, but I think next I'll try it out of a different pattern.
Here is the back with the elastic and the tie at the neck. The instructions/photos never show a picture of the back, so I thought it would be helpful for anyone who wants to make it to see the front and back. (there are no ruffles on the back - just on the front)