Prepare the garnishes: Have your sliced white onion, jalapeño slices, sour cream, coriander leaves and lime wedges ready before you start cooking so you can add them when you're finished.
Place the passata, chicken stock, oregano, onion and garlic powder, vinegar, sugar and chilli in a saucepan. Cook over a medium heat for 5 minutes. Add the shredded chicken, stir and cook for a further 1 minute. Remove from the heat, taste and season with salt and pepper to taste (the sauce should not be too thick, if it is, add a little water to loosen it up).
While the sauce is cooling, heat another frying pan with oil and, when very hot, break in the eggs. Fry until the edges are crisp, do not turn. Season with sea salt or this.
To serve: Stir the tortilla chips through the tomato chicken sauce to coat them well. Immediately divide into two bowls to prevent them from getting soggy. Top with fried eggs, onion slices, jalapeños, sour cream and coriander. Serve with lime wedges and extra chilli.