Crust

1. Combine the flour and salt in a food processor and pulse once. Remove the butter from the refrigerator just before using and slice the one stick of butter into small cubes. Add the butter and the egg yolk to the flour. Pulse the food processor until the mixture is the size of small peas (about 15 times). Then while the food processor is running, very slowly pour the ice water through the spout until the dough forms a ball. Remove the dough from the food processor and wrap in wax paper and place in the refrigerator for at least 1 hour.
2. Quickly roll out the dough to slightly larger than the size of the tart pan (see equipment note) to a thickness slightly less than a ¼ -inch. Flip the parchment paper and dough on to the tart pan and remove the parchment paper. 
3. Neatly tuck into corners and edges. Tear away the excess dough. 
4. Pierce the dough all over with the tines of a fork. Chill until ready to use.

Filling

1. Preheat the oven to 350℉.
2. Prepare an ice water bath. Shuck the fava beans, discarding the tough husks. Boil the fava beans in salted water for 2 minutes or so until the bright green beans start to turn pale yellow. Drain the beans and plunge into the ice water bath to cool. Finally, pinch the fava beans and using your fingernail, free the super-green fava bean from the exterior shell into a bowl. You might search for a Youtube video to see this process. It’s the love of Italian grandmothers!!
3. Peel and mince the shallot, cut the young pecorino into 1/4-inch pieces and remove the leaves from the marjoram stems and finely chop (about 1 tbsp).
4. In a medium-sized frying pan, melt the butter over medium-low heat. Add the minced shallot and sauté  until soft but not browned. Add the shucked and peeled fava beans, the white wine and a small pinch of salt and freshly ground pepper. Gently cook until all the wine has evaporated. Add the chopped marjoram and stir. Let cool to room temperature.
5. Stir the cubed pecorino in with the fava beans and evenly distribute in the prepared chilled tart pan.
6. Into a bowl, crack the eggs and add the grated pecorino and whipping cream. Add a pinch of salt and pepper. Whisk until combined.
7. Pour over the prepared tart until the egg mixture comes to about 1/8-inch from the top of the crust.
8. Bake in the preheated oven for 30-40 minutes at 350 degrees until the top is lightly browned.
9. Let cool to room temperature then remove from the tart pan. Cut into squares and serve.