Preheat the oven to 350 degrees.
In a large skillet over medium heat, melt the butter and add the onion, garlic, bell peppers, and jalapeno. Stir and cook for 5 minutes, until the veggies are soft and golden. Remove the skillet from the heat to let the veggies cool slightly.
In a mixer, combine the cream cheese, mayo, sour cream, and 2/3 of the cheese. Mix with the paddle attachment on low until combined. Add the green onions, the veggie mixture, the corn, and the green chilies. Mix on low until just combined.
Spread the mixture in a baking dish and top with the rest of the cheese. Sprinkle top lightly with chili powder. Bake for 20 to 25 minutes, until bubbly and golden. Remove from the oven and serve warm with tortilla chips. To save a few calories, cut up veggies are excellent for dipping instead of chips.