In a large bowl (regular or the bowl of a stand mixer,) whisk the flour, salt Italian seasoning, garlic powder, and yeast together. Make a well in the center and add water warm and oil; stir until a shaggy dough forms.
Use the dough hook on the stand mixer and knead he dough for 3 to 4 minutes. If hand mixing, turn dough out onto lightly floured surface and knead until the dough is soft and smooth, about; 6 to 8 minutes. Add small amounts of flour if the dough is too sticky.
Form the dough into a ball and place in a lightly oiled bowl, cover and let rise for 30 to 60 minutes, or until almost doubled in size. With instant yeast, and depending how warm my kitchen is, it takes about 30 minutes.
Preheat the grill or grill pan to medium heat (350 to 400 degrees F) just before the dough is ready. Divide the dough into 2 to 4 even pieces and shape into ovals (they don't have to be perfect!) and brush one side with olive oil.
When the grill is ready, place the dough onto the grate, oiled side down. Grill for 3 to 4 minutes or until the underside is golden. While the first side cooks, brush the side facing you with olive oil. Flip the flatbread and continue grilling for another 2 to 3 minutes or until golden. While it's grilling, add desired toppings and close the lid for a minute or two to trap the heat.
Notes
Topping Ideas: For this flatbread, I used:
8-ounces fresh mozzarella cut into thin slices
1/2 cup shredded mozzarella
olive oil
3 thinly sliced Roma tomatoes
1/2 cup fresh basil (torn leaves and whole)
Making Flatbread Ahead: This dough can be prepared ahead. Let the dough rise until doubled, then deflate and divide into equal portions. Wrap in plastic wrap, store in an airtight container, and freeze for up to 3 months. Thaw the dough overnight in the refrigerator and let it come to room temperature on the counter before shaping into ovals and grilling.