Recipe courtesy of Dan Weinreich. I had to take a picture of this before it went into the oven, because after it came out it disappeared!
1/3 cup salted butter
1 cup flour
3 TB Dijon mustard
2 or 3 large juicy tomatoes
1 pound mozzarella
3 cloves garlic minced
salt, pepper, oregano, olive oil
Roll out single pie crust (cut butter into flour, add ~3.5 T ice water so ball holds together, refrigerate 1+ hour) to fit pan. Spread Dijon mustard over the floor of the pan. Build two layers, each consisting of sliced mozzarella, thinly sliced tomatoes, salt, pepper, oregano and minced garlic. Drizzle top layer with olive oil. Bake 40 minutes at 400F. Let sit at least 20 minutes, though also excellent at room temperature.