Heat the oil in a medium saucepan and sauté the diced onion for 2-3 minutes until soft. Add the shredded chicken, chilli beans, chopped tomatoes and mustard and simmer for 5-8 minutes until thick and saucy.
Combine the chopped cherry tomatoes, diced avocado and finely diced red onion, drizzle with a little olive oil and season well. Combine the sour cream, mustard, then squeeze over lemon juice, mix well. Arrange the corn chips in a bowl and spoon over the spicy chicken and beans, top with avocado salsa. Drizzle with the mustard sour cream and top with a few sprigs of fresh coriander.