First make the dough. Sift together flour and salt in bowl. Add small cubes of butter and blend together in food processor until it looks like small peas.
In another small bowl, whisk together sour cream, lemon juice and water and add this to flour mixture. Using a spatula or your hands, mix together until everything forms into a ball. Don't overwork dough. Wrap in plastic wrap and refrigerate for at least 30 minutes.
Next prepare the filling. Cut zucchini into thin slices. I used my slicing attachment on my food processor and prefer thinner slices. Lay all the slices on a single layer on paper towels and sprinkle with salt. Allow to sit while you prepare other filling. Blot with paper towel to remove excess moisture.
In a small bowl, whisk together olive oil and garlic and set aside. In another bowl, mix together ricotta, Parmesan cheese, thyme, salt and pepper and 1tsp of olive oil mixture. Set aside.
Pre-heat oven to 400 degrees. On a floured surface (VERY floured) roll dough out to about 12 inches round. Transfer dough to baking sheet with lined parchment. Spread ricotta filling evenly leaving a border.
Lay zucchini on top of ricotta mixture in a circular pattern, starting outside. Drizzle remaining olive oil on top. Fold the border over and pleating so everything is tucked.
Bake at 400 for about 30-35 minutes until crust is golden brown.