01 - Heat 1 tbsp vegetable oil in a large skillet over medium heat. Add the diced chicken and cook until no longer pink throughout, approximately 4 to 5 minutes.
02 - Add the chopped onions and diced carrots to the skillet. Sauté until softened, about 3 minutes. Stir in the frozen peas and cook for 1 additional minute.
03 - Add the cold cooked rice to the skillet, breaking apart any clumps with a spatula or rice paddle. Toss everything together until well combined.
04 - Pour in the ketchup and soy sauce, stirring thoroughly until the rice is evenly coated and heated through. Season with salt and pepper to taste. Remove the fried rice from the pan and shape into two oval mounds on serving plates.
05 - In a mixing bowl, whisk together 2 eggs, 1 tbsp milk, and a pinch of salt until fully blended. Repeat with the remaining 2 eggs and 1 tbsp milk when ready for the second omelette.
06 - Melt 1 tsp butter in a nonstick frying pan over medium-low heat. Pour in half of the egg mixture, swirling gently to coat the pan evenly. Cook while stirring softly until the edges are set but the center remains slightly runny.
07 - Carefully slide the soft omelette out of the pan and over one of the shaped rice mounds, letting it drape naturally over the rice. Repeat the omelette process for the second serving.
08 - Drizzle extra ketchup over each assembled omurice and garnish with fresh chopped parsley if desired. Serve immediately while warm.