The Shakers wasted nothing, and they used whole lemons in this pie bar. That’s right–rind, pith, and all go into the filling. Be sure to slice the lemons as thin as you can and let them macerate in sugar for at least 3 hours (the longer, the better). The result is a tart lemony filling similar in texture to marmalade. You can substitute regular lemons, if Meyer lemons are not in season.