2) Trim the top and bottom off the grapefruit to expose the inner fruit. Following the curve of the fruit, cut off the skin and white pith. Cut the segments free from the membrane and add to the dressing. Repeat with the oranges. (For help with this, see our video demo of segmenting an orange.)
3) Add the jalapeno, jicama and fresh coriander to the citrus mixture. Drain the onions and stir to combine evenly.
4) Preheat the grill to high and position a grill pan about 14cm below. Lightly brush the salmon with some olive oil. Sprinkle the top of the fish with the chilli powder and season with salt, to taste. Carefully lay the fish, skin-side down, on the hot grill pan.
5) Grill the fish until just firm and brown, about 7 minutes. Remove the pan from the grill; set the salmon aside on the hot pan to finish cooking, about 5 minutes more.
6) Divide the fish among plates and serve with the salsa and tortillas.
Cook's Note: Our favourite way to warm tortillas is in the microwave. Wrap the tortillas in paper towels and heat on full power until pliable and hot, about 30 seconds.