Swiss Chard and Potato Crostrata

My admiration for Lidia Bastianich started with my grandmother.  She would watch the show and then tell me all about the food that was made.  The irony was that my grandmother was so like Lidia if the two cooked side by side, you would not be able tell the two apart.  My sweet grandmother passed away more then a decade ago and when I miss her so much it hurts, I find myself watching Lidia and feeling comforted.  I came across this recipe during my latest Lidia-fest and the result was superb.  I never made a crust with oil and I had doubts through the entire process but sure enough, the result was a flaky crust that had the flavor of olive oil and held the filling well.  I noticed that it did not brown like butter crusts do but it was indeed baked through.

Swiss Chard and Potato Crostata (adapted from Lidia's Mastering the Art of Italian Cuisine 2015)
Serves 8-12

Dough
240 grams ap flour, more for rolling the dough
1/2 tsp kosher salt
1/2 cup olive oil
1/3 cup cold water

Filling
1 bunch Swiss Chard, about 1 1/2 lbs, washed and drained
2-3 potatoes, about 1 1/2 lbs total, cooked and mashed
1 cup heavy cream
3 Tbsp olive oil
4 large eggs
2 tsp kosher salt
2 cups grated Fontina or Asiago
1 cup finely grated Parmesan

For the dough: In a food processor, combine the flour and salt, and pulse.  Mix the oil and water together, and with the machine running, add oil mixture in.  Process to make a soft dough, about 30 seconds.  The dough should be soft and sticky to the touch. 
Dump the dough on a lightly floured work surface and knead for 1 minute until the dough is very smooth.  Let rest on work surface, covered for 30 minutes. 

For the filling: Bring a large pot of salted water to a boil.  Meanwhile cut the chard stems into 1 inch pieces and the leaves into 1/2 inch strips.  When the water boils, add the stems and cook for 10 minutes.  Add the leaves and cook for another 15 minutes.  Drain and set aside to cool. 
Combine the heavy cream, oil, eggs and salt and mix to combine.  In a large bowl, combine the potates, and chard, then add the cream mixture.  Finally, stir in the cheeses.  Set aside. 
Preheat the oven to 375 degrees.  On a lightly floured work surface, roll the dough to fit a rimmed half sheet pan with about 3 extra inches on all sides.  Lightly butter the pan and fit the dough into the sheet pan with the ends of the dough hanging off the sides.  Spread the filling evenly over the dough.  Fold the overlap of dough over to form a 2 inch crust around the pan, leaving the center without a crust.  Bake until the filling is set and the crust is baked though, about 40-45 minutes.  Cool on a rack.  Serve slightly warm or room temperature.  Enjoy!!