In a bowl, mix together pork, half of the cooking oil, the sugar and Mexican seasoning. Set aside to marinate for 30 minutes.
Meanwhile, preheat oven to 160°C.
Heat a griddle pan over high heat. Coat pan with oil spray and cook pineapple rings for 1 minute per side. Halve and set aside.
To make slaw, in a large bowl add cabbage, carrot and mayonnaise. Mix thoroughly to combine and set aside.
In a baking tray, combine pumpkin seeds and olive oil. Season well with sea salt then bake in oven for 8 minutes until seeds puff and turn golden.
Meanwhile, heat remaining cooking oil in a frying pan over high heat. Add marinated pork and cook, stirring regularly, for 4–5 minutes until just cooked through.
To assemble, divide slaw evenly between tacos. Build each taco with grilled pineapple, pork and sliced avocado. Top with toasted pumpkin seeds for crunch and serve.