Preheat oven to 425F
Heat 1-2 tablespoons of neutral oil (i.e. vegetable) in a large skillet over medium heat
Cut onion into rings or chop coarsely
Toss them into pan and cook for 10-15 minutes, till they're soft and golden brown. You probably want to reduce the heat a bit after a while. Stir them every once in a while
Finely dice the garlic
Toss it in the with the onion and cook for a minute or less. stir often. sprinkle with salt and then pull this stuff out of the pan onto a plate
Meanwhile, you've been cutting the tomatoes in half or slices, and you've sprinkled those with salt too
Grate or break up your cheese as appropriate
Break the egg into a small bowl, add a tbsp of water, and stir it up to make an egg wash
Roll out your dough to a circle like 12" in diameter. Place this on parchment paper onto a sheet or jelly roll pan
Pile up the onion mix, then the tomatoes in the center of your dough, leaving a few inches border
Top with cheese
Fold up the extra dough around the sides of the filling to contain it as best you can
Brush the outer edges of the dough, which are now facing up, with the egg wash
Bake for maybe 20 or 25 minutes, until the crust is nice and golden
Top with chopped herbs and serve
