Place the tortilla chips on a tray lined with baking paper, top with the onions and sambal oelek. Sprinkle the Manchego over the top.
Bake for approx. 5 mins. in the upper half of an oven preheated to 220°C, remove from the oven. Sprinkle with coriander.
Mash the avocado with a fork, add the lime juice and sambal oelek, season. Serve with the nachos.