Place corn (still in the husks) into the oven and roast for 30 minutes. (You can also do this on the grill.)
Take the corn out of the oven. Once cool enough to touch, remove the husks and cut the kernels from the cob. Set the corn aside to cool.
In a medium bowl, mix together the cream cheese and Greek yogurt until smooth. Add the cheddar cheese, corn, black beans, jalapeno, green chilies, garlic powder, cumin, salt, and pepper. Mix to combine.
Cover and store in the refrigerator until ready to serve. Sprinkle some sliced green onions over the top of the dip and serve with crackers, pita chips, or tortilla chips.
Notes
If needed, you can pan-roast the corn. Grab 1-2 cups of canned corn that's been drawing or frozen corn that's been thawed. Add the corn to a large skillet over medium-high heat. Cook for 6-8 minutes until the corn is slightly charred and has a popcorn-like smell. (Be careful. The corn kernels will start to pop out of the pan.)