Line a baking sheet (minimum dimensions 17x11.5 inches) with parchment paper, drizzle with olive oil and spread it out evenly with your hands. Turn the schiacciata dough out onto the baking sheet. Using slightly wet or oiled hands, pull and stretch the dough out into an even square/rectangle (or whatever shape you can manage; it can be a little challenging to spread out), pulling from the underside of the dough outward. Dimple it with your fingers (keep your fingers moist to keep them from sticking).
Let rise for at least 1 hour while the oven is preheating to 475° F (245° C).
Prep all your vegetables by cutting and patting dry of any excess moisture.
Drizzle the focaccia with olive oil and salt well with a flaky salk like Maldon.
Now you can feel free to decorate! Try not to press the veggies down too much into the dough. Just gently place them onto the dough, being sure they are indeed sticking to the dough and not popping or curling up (can happen depending on how you cut the vegetables).
Bake for 13-17 minutes in the middle of the oven until golden brown and crunchy.
Let cool before cutting.