Roasted Tomatoes: Preheat oven to 300°F (150°C). Toss tomatoes in a baking pan with olive oil, Italian herbs, salt, and pepper. Roast for 45 minutes - 1 hour until they're softened and slightly caramelized but still hold their shape. Set aside
Walnut Pesto: In a food processor, combine basil, toasted walnuts, garlic, Parmesan cheese. Pulse until coarsely chopped. With the processor running, slowly drizzle in olive oil until smooth. Add lemon juice and season with salt and pepper. Set aside.
Breaded chicken: Slice your chicken breast into 2 pieces length-wise. While working with 1 piece at a time, cover the chicken with a piece of plastic wrap and using a meat tenderiser, flatten out the chicken into a thin even piece. Repeat with the other piece. Season the chicken with salt and pepp.
Add your breadcrumbs onto a plate and mix in the parsley, onion powder and garlic powder. Prepare your breading station. Working with 1 piece of chicken at a time, place the chicken into your flour and cover it well. Transfer the chicken to your beaten eggs and cover it well. Transfer the chicken to your seasoned breadcrumbs and press it in well. Repeat with the 2nd piece.
Bring a pot of oil to frying temperature (180C/ 350F). Carefully drop in 1 piece of breaded chicken at a time and fry for 4-6 minutes, depending on the thickness of the chicken and flipping halfway, or until golden brown. Place on a wire rack to drain.
Assemble: On 1 piece of toasted bread, spread on a layer of the walnut pesto, then top with a piece of chicken. Break apart a burrata cheese ball and top with the roasted tomatoes. Close the sandwich. Enjoy!