1Finely chop mushrooms by hand, or alternatively, pulse in a food processor until finely chopped.
2Heat oil in a saucepan over medium heat. Add onion and fajita seasoning, cook until softened. Increase heat to high, add mushrooms and mince, cook, breaking up mince with a wooden spoon, for 8-10 minutes until browned. Add tomato salsa and bring to a simmer. Reduce heat to low, a simmer for 15 minutes or until sauce thickens.
3Preheat oven to 180°C fan-forced. Line a baking tray with baking paper. Arrange tortilla strips over base of tray. Sprinkle three-quarters of cheese over tortilla strips. Top with mince mixture. Sprinkle with remaining cheese. Bake for 10 minutes or until cheese has melted and tortilla strips heated through. Top with mashed avocado, sour cream, chopped pickled jalapeno & chopped fresh coriander leaves. Serve.