We took some of our favorite lasagna ingredients – ricotta cheese, spinach, thyme and Asiago cheese – but instead of layering them with noodles, we mixed them together in a rich, but still light tart filling. With a store-bought crust, the tart can be in the oven in 20 minutes and on the table 40 minutes later. And similar to a good quiche, this tart can be served hot or room temperature.