Preheat oven to 425°F. Line a baking sheet with parchment paper.
Make the filling. Scoop the avocado out of the skins, discard the pits, and place in a small mixing bol. Add the tomato, onion, lime juice, zest, cilantro and salt Mix until well combined, leaving small chunks of avocado in the mixture.
Assemble the wontons. Add some cold water to a ramekin or small bowl. Working with one wonton wrapper at a time, scoop about a tablespoon of the avocado mixture into the center of the wonton wrapper. Using your finger, run water along the edge of the wrapper that's facing up. Fold the wrapper so the corners meet, making a triangle shape Press edges together. Place the wontons in a single layer on the baking sheet and continue to repeat the process until all of the avocado mixture has been used. You should end up wth 12 - 14 wontons.
Spray the wontons with olive or avocado oil and bake for 8 minutes. After 8 minutes remove from the oven and carefully flip the wontons over. Bake for an additional 7-8 minutes until the edges are a dark golden brown. Remove from oven and let cool for about 5 minutes.
While the wontons are cooking mix the yogurt, zest, cilantro, cumin, lime juice and salt in a small bowl. Refrigerate until ready to serve.
Serve the wontons warm or refrigerate until ready to eat. If refrigerating reheat for 5-10 minutes in a 250°F oven.