To make the crust
1. Combine the first 5 ingredients in a food processor fitted with the “S” blade. Pulse to combine until the butter is incorporated and the mixture appears grainy. Add the egg to the food processor and pulse until completely incorporated. Gather a bit of the dough mixture in your hand, press tightly, and test to see if the mixture is moist enough to hold together. If it is still very dry add a tablespoon of water and pulse again.
2. Lay a few sheets of plastic wrap on the counter and pour the dough onto it. Use the plastic wrap to help you form the dough into a round disc shape. Wrap tightly and place in the refrigerator for 1 hour or up to overnight.
To make the filling
1. If you refrigerated the dough overnight remove the dough from the fridge and place it on the counter to warm up a bit while you make the fillings. This will make it easier to roll out.
2. In a small bowl combine the ricotta, orange zest, and tea. Stir until completely incorporated; set aside.
3. In another bowl combine the sliced strawberries, sugar, and vanilla beans, stir well and set aside. The sugar will turn into a syrup as the berries macerate, so you will need to stir a few times as it sits to make sure that all of the sugar is dissolved.
Build the galette
1. Preheat the oven to 400°F and line a baking sheet with parchment. Set aside.
2. Line your kitchen counter with parchment paper. Place the dough on top then cover the dough with another piece of plastic wrap or parchment. Use a rolling pin to roll the dough into a very thin circle about ⅛-inch thick and 14-17 inches in circumference.
3. Spread the ricotta mixture onto the dough leaving a 1½ inch border all the way around the dough. Top the ricotta with the sugared strawberries then sprinkle the raspberries over the top.
4. Using the edges of the parchment paper that are underneath the dough, gently fold the edges of the dough over the filling creating a crust that looks a bit like a pizza. The dough is very fragile and it may tear in spots, you can gently use your fingertips to press the dough back together.
5. In a small bowl combine the egg and water. Beat until pale yellow and completely combined. Use a pastry brush to brush the raw edges of the galette crust with the egg wash. Sprinkle granulated sugar liberally over the edges of the dough.
6. Once the galette is completely formed carefully transfer the galette to the prepared baking sheet and place in the freezer for 10-15 minutes for the dough to firm back up.
7. Bake the galette in the preheated oven for 10 minutes then reduce the heat to 350° F and bake for an additional 25 minutes until golden brown.
8. Remove the galette from the oven and allow to cool for 15-20 minutes before slicing. This will allow time for the filling to set.
Serve warm or room temperature with a sprinkling of powdered sugar and a scoop of ice cream if desired.