Preheat the oven to 150°C.
Place cut tomatoes on a roasting tray and drizzle with olive oil.
Season with salt, pepper, and half of the thyme leaves.
Roast for 4 to 6 hours until dried, then allow to cool in the turned-off oven overnight.
Blitz breadcrumbs, parmesan, lemon zest, and remaining thyme in a food processor.
Butterfly the chicken breasts to double their size and halve their thickness.
Dust the seasoned chicken breasts in flour.
Dip the chicken into the beaten egg and then the breadcrumb mixture to coat thoroughly.
Fry chicken in oil and butter over heat for 2 minutes per side until golden.
Serve chicken with roasted tomatoes, watercress, and lemon wedges.