Step 1

Preheat oven to 350F. Lightly butter a 9-inch tart pan with a removable bottom.

Step 2

Add the flour, salt and butter to the bowl of a food processor and pulse until crumbly, and no large pieces of butter remain (small pieces are fine)

Step 3

Slowly add the cold water through the top of the processor and continue to pulse until the dough comes together into a single clump. Note: you can also do this by hand with a pastry cutter.

Step 4

Remove the dough to a lightly floured surface and divide in half. Save the other half of the dough for another recipe (I like to wrap mine tightly in plastic and freeze it)

Step 5

Roll out the remaining half of the dough into a large circle big enough to fit your tart pan.

Step 6

Lay the dough over your tart pan and press it up the sides, removing any excess. Prick the bottom all over with a fork, and weigh down the bottom by placing a piece of parchment paper over the bottom and topping it with dried beans or rice, or pie weights.

Step 7

Bake for about 15 minutes. Remove and allow to cool while you prepare the filling.

Step 8

In a small bowl, mix together the mayonnaise, sliced onion, one cup of the cheddar cheese, salt, and pepper. Spread the mixture over the bottom of the partially baked pie crust.

Step 9

Follow by adding the thinly sliced zucchini in overlapping concentric circles.

Step 10

Lightly brush the top of the zucchini with olive oil, and top with the remaining shredded cheddar.

Step 11

Bake for about 20-25 minutes until the cheese is starting to turn golden brown. I put mine under the broiler for a few minutes at the end.

Step 12

Remove, allow to cool slightly, top with fresh thyme sprigs and fresh cracked black pepper.