Combine the flours and salt in a food processor and pulse to combine. Add the butter and pulse until the mixture is crumbly and pea-sized. Add the ice water and thyme, and run until the dough comes together into a ball, roughly 30 seconds. Form the ball into a slightly flat disc shape, wrap in plastic wrap and refrigerate for at least 30 minutes.

Preheat the oven to 400F. On a well floured surface, roll the dough out into a large rectangle, about 1/8 inch thick, turning the dough 1/4 after every couple of rolls and flouring underneath as you go, to prevent sticking. Carefully roll the dough onto the rolling pin, and transfer to either a standard 9.5 inch tart pan, or a 35x11cm long pan. Return the crust to the freezer for 10 minutes, then prick with a fork and blind bake (bake empty) for 10 minutes. Let cool slightly.

Reduce oven temperature to 375F. Layer the bottom of the tart with cheese, then layer the tomatoes over top, being sure to overlap. Season the top with salt and pepper, and bake for 30-40 minutes or until tomatoes are cooked and beginning to brown. Let cool 5-10 minutes before removing from the pan. Serve warm or cold, with a drizzle of honey and additional thyme if desired.