Add the potato wedges to a pan of water and set on a medium heat. Bring to the boil and cook for 5 minutes until the wedges are just softening. Drain well.
Preheat the oven to 190ºC. To a bowl, add the garlic granules, onion powder, paprika, cumin, oregano and chilli flakes. Add a little salt and pepper and stir to combine.
Add the potato wedges to a baking tray and spray with low-calorie cooking spray. Sprinkle over the spices and pop into the oven for 25 minutes until golden brown.
While the wedges are cooking, combine the avocado, cherry tomatoes, garlic, chilli, lime juice and 1 spring onion in a mixing bowl. Season with a little salt and pepper and leave until ready to serve.
Sprinkle the grated cheese over the wedges and cook for a further 3 minutes until melted and bubbly.
Divide the wedges between 4 serving plates, add a spoonful of the avocado mix and drizzle over some sour cream. Sprinkle with the remaining spring onion and serve.