First, you need to season the chicken breasts with salt and pepper.
Heat up the vegetable oil in a large skillet over medium heat. When the oil is hot, add the chicken breasts to it and cook them for about 10 minutes or until they are browned on both sides. Once cooked, remove from heat and transfer to a plate lined with paper towels, and let cool.
While the chicken is cooling, in a large bowl combine mayonnaise, Greek yogurt, mango chutney, curry powder, tomato ketchup, Worcestershire sauce, and lemon juice; mix well so all ingredients are evenly distributed.
Cut the chicken breasts into cubes or strips and add to the dressing mixture; toss to evenly coat.
Finally, add the toasted almonds, sultanas, and cilantro; mix well so everything is evenly distributed. Cover and chill for at least 30 minutes before serving.