Measure the parchment paper to be double the size of the skillet. Place the tilapia in the middle of the parchment paper and season both sides with the chili powder and salt.
Place the skillet on the stove and pour water into the skillet to be ½-inch high. Turn the heat on medium low. When the water begins to boil, pick up the parchment paper with the fish on it and place it in the skillet, in the water. Put the lid on top and let it steam for 5 minutes.
Remove the lid, then remove the parchment paper from the skillet and set aside. Let the fish cool.
Rinse the cilantro with water and pat is with a paper towel to remove the excess water. Let it sit on the paper towel to drain.
Chop the tomato into ¼ to ½-inch thick pieces (makes about 3 cups). Add it to the bowl.
Chop the onion into ¼-thick pieces (makes about ½ cup). Add it to the bowl.
Remove the cilantro leaves from the stems and finely chop the leaves until you have ? to ½ cup. Add it to the bowl and stir everything together well.
Chop the avocado into ¼ to ½-inch thick pieces. Add it to the bowl.
Place the fish in a separate bowl and break it into small pieces with a fork, then add the fish to the large bowl.
Cut the lime into 4 wedges and squeeze 2 wedges into the bowl, and add the salt. Lightly stir the pico together and taste. Add more lime as desired. Salt to taste.