Cut ajis/chili coarsely, remove seeds and veins. Place them in a saucepan with water and bring to a boil. Strain and repeat boiling 2 more times. Blend with little water if necessary.
Combine tomato paste, chili, water, vinegar, salt and garlic in a large bowl. Pour over chicken and marinate for 6 hours or more.Place chicken breasts, skin side down, on a horizontal surface. Remove fillet from each breast and reserve them for another use. Place chicken on a lightly greased baking pan in a single layer.
Place 1 tomato slice on each chicken breast and sprinkle rosemary on top . Fold chicken over to enclose tomato and rosemary, like a sandwich. Secure chicken ends with a skewers or toothpicks.Brush oil and heat skillet. Brown chicken on both sides. Transfer chicken breasts to a baking pan and finish cooking in the oven 350°F (180°C).This chicken can be grilled. Remove toothpicks to serve.