Preheat oven to 200C (180C fan-forced). Lightly spray 2 baking trays with oil. Arrange tortilla triangles in a single layer on trays. Lightly spray with oil. Bake for 5-6 minutes or until golden. Cool on a wire rack.
Meanwhile, heat oil in a large frying pan. Cook onion, stirring, for 5 minutes or until soft. Increase heat to high. Add turkey mince and cook, stirring to break up any lumps, for 3 minutes or until browned. Add ground cumin, coriander and chilli and cook, stirring, for 1 minute. Stir in beef stock, beans and tomato paste and bring to the boil. Gently boil for 10 minutes or until thickened.
Meanwhile, combine yoghurt, garlic, rind and juice in a small bowl. Season. Combine avocado, tomato and coriander in a small bowl.
To serve, arrange tortilla chips on a platter. Spoon over turkey mixture. Sprinkle with cheese. Cook under a preheated grill for 1-2 minutes or until cheese melts. Sprinkle with avocado mixture and serve with a dollop of lime yoghurt.