Remove the rosemary needles from the sprig and roughly chop. Combine the chopped rosemary, panko & regular bread crumbs, garlic powder, onion salt, and pepper in a food processor. Mix 2 tablespoons of olive oil into the mixture.
Mince the shallot and slice the garlic cloves and set aside. Quarter the tomatoes and place in a bowl (try to keep as much of the tomato juice as possible).
Heat 2 tablespoons of olive oil in an ovenproof skillet over medium heat and preheat the oven to 350 degrees. Add the tomatoes to the skillet; allow to cook until juices start to bubble (about 2 minutes) then add in shallots and garlic. Allow to cook down for another 2 minutes.
Slice the zucchini into thin rounds and layer on top of the tomatoes. Sprinkle the breadcrumb mixture over the top and bake for 20-25 minutes, or until zucchini is tender and breadcrumbs are toasted.