Preheat the oven to 410º F (210º C).

In a medium-sized Pyrex bowl, combine the butter, oil, water, sugar, and salt. Place bowl in the preheated oven for 15 minutes, until the mixture is bubbling and brown around the edges.

Using an oven mitt, remove bowl from oven and pour the flour into the butter mixture. Stir until the dough comes together and forms a ball.

Transfer the dough to a 10 or 11-inch tart pan with a removable bottom. When the dough has cooled down a bit, set aside a small piece of dough and then press remaining dough into an even layer with your fingers.

Pierce the bottom with a fork all over. Bake for 15 minutes or until crust is golden brown.

Remove from the oven. Use the reserved dough to patch up any cracks that might occur during baking. Allow to cool before filling.

Reduce oven temperature to 375˚F. Place a sheet pan on the middle rack.

While the crust is cooling, combine eggs, ricotta, half and half, Italian seasoning and salt. Mix well to combine then add basil leaves and stir gently.

Slice tomatoes into quarter-inch slices and place on several thickness of paper towels to drain.

Add mozzarella to cooled crust and spread to an even thickness. Pour egg mixture over the top. Bake on heated pan for 10 minutes.

While tart is baking, brush tops of tomatoes lightly with olive oil. After 10 minutes, remove tart from oven and arrange tomatoes over the top. Sprinkle lightly with sea salt or kosher salt and freshly ground black pepper.

Return to oven for another 15-20 minutes or until just set and center no longer wiggles when pan is gently shaken. Allow tart to set up for 10 minutes before serving. Serve warm or at room temperature.