This crunchy, jammy tart is a wonderful little summer dessert. It's fuss-free, prep-free, and turns out reliably delicious every time. It's basically what I want a pie to be like, but much easier and quicker to make. The cornmeal adds a nice nuttiness and texture, and the sweet-but-not-too-sweet blueberry filling is juicy without being runny. You can bake it ahead of time in a pie plate, cake pan, or tart pan, and easily transport it to your next summer party.