Preheat the oven to 350 degrees. Line a baking sheet with aluminum foil and grease with a dab of oil.
Mix flour, salt, and lemon pepper. Dredge the chicken breasts in the flour mixture, then coat with the egg. Cover the chicken in the panko breadcrumbs and place on a baking sheet.
Bake for 15-20 minutes until cooked through.
Heat the oil over medium heat and add the garlic. About 30 seconds to 1 minute later, add the tomatoes and cook for another 2-3 minutes. Add in some green onions (reserve some for decoration, if you want) and cook for another minute or so.
Pour the sauce over chicken breasts, garnish with remaining green onion and tomato halves.