Blend the flour and the kosher salt in the food processor on low for 3 seconds

Cut the chilled butter into ¼ inch cubes, add it to the food processor and pulse until you have a course meal texture. For me this is about 5 pulses for 1 second each

Empty the flour mixture into a bowl and add the apple cider vinegar then the ¼ cup of ice water and mix quickly with a fork

Continue adding ice water by the tablespoonful until the dough is shaggy or just wet enough that it just starts coming together with some pieces still hanging off

Pull the dough together with your hands and knead it on the counter top 4 times. Do not over mix

Press the dough into a disk and wrap it tightly with plastic wrap. Refrigerate the dough for at least 1 hour and up to 2 days

Slice the heirloom tomatoes and set them in a medium sized bowl

Add 1 tsp of kosher salt, mix well and let sit for 10-15 minutes

Layer paper towels on a plate or the counter top and lay the heirloom tomatoes flat on the towels to soak up any extra liquid

Press another layer of paper towels over the top of the tomato slices to soak up the juices from the top as well

While the tomatoes are drying, shred the sharp white cheddar and parmesan cheeses

Mince the garlic and set it to the side

Pick the thyme off the stems, rough chop it and set it aside

Slice the chives and set them aside

Preheat the oven to 400°F and line a baking sheet with parchment paper

After the galette dough has been in the fridge for at least 1 hour, take it out and roll it out on a lightly floured surface until it's 14-16 inches around. It doesn't need to be perfect by any means

Then transfer the galette dough to the parchment lined sheet tray

Top the dough with the sharp cheddar and parmesan, leaving a 2 inch border around the edges

Sprinkle the fresh thyme over the cheeses

Rub the garlic onto the heirloom tomatoes and layer them on top of the cheeses

Sprinkle the black pepper over the top of the heirloom tomatoes

Fold up the edges of the crust going around in a circle

Whisk the egg and brush it over the top of the crust edges, sprinkle the edges with a pinch of kosher salt and black pepper

Bake until the crust is a medium golden brown color. Top with fresh chives and basil. Serve hot or room temp