Preheat the oven to 180°C/350°F (160°C/320°F if using a ventilated oven).
Rinse the gilthead sea breams inside and out under running water, then pat them dry with a paper towel.
Finely chop the parsley.
Season the fish with salt and pepper, including inside, and stuff them with the parsley.
Slice the garlic into strips and place it inside the fish as well.
Cut the cherry tomatoes into quarters, season them with salt and pepper, and stuff them into the fish.
Place the fish on parchment paper (I baked them along with the potatoes and cherry tomatoes), drizzle with a little oil, and lightly season with salt. Bake in a preheated non-ventilated oven for about 25 minutes (20 minutes in a ventilated one), or until both fish are cooked through.