Place the walnuts in a food processor and mix to give a coarse crumb. Repeat with the mushrooms and mix into the walnuts.
Heat the oil in a large saucepan and fry the walnut mixture and garlic for 5 minutes. Add the spices and cook for 1 minute.
Stir in the tomatoes, tomato puree and both beans and cook gently for 10 minutes, stirring occasionally. Season and stir in the coriander.
Place the tortilla chips on a large heatproof plate, top with the chilli mince. Sprinkle with Tex Mex cheese and grill for 2-3 minutes. Top with guacamole and tomato salsa and sprinkle with extra chopped Walnuts to serve.
