For the fry bread
Combine first three ingredients in a bowl. Cut in the shortening until thoroughly blended in. Add the water and stir just until a loose, sticky dough forms. Transfer the dough to a lightly floured surface. Flour your hands, and then knead and shape the dough into a foot-long log. Cut the log into 8 equal pieces. Press each piece into a disc that’s about 5" wide. Now prick each disc a few times with a fork.
Heat 1" of the oil in a large skillet set over medium to medium-high heat. When hot, fry one disc of the dough for 45 to 60 seconds. Carefully turn over and fry the bread 30 to 45 seconds on the other side, or until puffed and golden. Drain on paper towel and then set on a baking sheet. Cook the remaining fry bread in this fashion.
For the tacos
Place the first 5 ingredients in individual bowls and set on a platter. Refrigerate until needed. Preheat the oven to 425°F. Cut the salmon into 1" long by 1/4" thick strips and place in a bowl. Add the oil, 2 Tbsp. lime juice, brown sugar and spices and toss to combine.
Arrange the salmon in a single layer on a parchment paper-lined baking sheet; season with salt and pepper. Bake for 8 to 10 minutes, or until just cooked through.
Remove salmon from the oven, and then pop fry bread into the oven to warm for a few minutes. Place the fry bread in a basket and serve alongside the platter of toppings and the salmon. Now let diners top their fry bread as desired.