Preheat oven to 500F. Place the dough in a large bowl and add the seasonings (garlic powder, dried oregano, dried basil and dried thyme) and salt. Knead until the seasonings and salt are well incorporated.
Roll the dough out onto a floured surface. Use your fingers to lightly press the garlic slices into the top surface of the dough. Bake the focaccia until the dough is puffed, blistered, and browned (about 8-10 minutes).
Remove the focaccia front he oven and lightly brush it with olive oil (optional. Top it with the tomato halves, chopped basil, and a pinch of salt to taste.