This is an easy family favorite, the Pizza Rustica agli Spinaci...or Spinach Pie. Even my older son digs into this meal...and he hates anything even remotely GREEN. The crust is Puff Pastry and here's a recipe, but I'm usually just too lazy to make it from scratch. I can get it readymade at the supermarket for about €1.45 and, for me, it's worth it.
So, step one for me is - take the puff pastry out of its packaging and lie it across your tart pan. You can also use a standard pie pan. It depends on whether you prefer a deeper or shallower pie.
Step two - prepare the pie filling.
some frozen spinach (thawed and excess water removed)
some ricotta (150 grams?)
some grated cheese (Parmigiano, Grana, Pecorino, as you prefer)
salt (to taste)
pepper (if you like it)
Blend the above ingredients all together in a deep bowl with an electric blender. Pour them into the pastry shell and bake until brown (about 30 minutes) at 180° Celsius (about 375° Farenheit).
If you like, you can add other cheeses, either cubed or grated, or diced ham. This is one of those recipes where you can follow my mother-in-law's advice and "throw in whatever you have in the refrigerator"!