Preheat oven to 350°F.
Put corn in a large, dry, nonstick skillet over medium-high heat. Season with salt and pepper, and cook until it starts to brown, 5-7 minutes. Transfer to a large bowl.
Melt butter in the pan. Add onion, bell pepper and jalapeno and season with salt and pepper. Cook until softened, about 8 minutes. Stir in garlic and chili powder and cook until fragrant, about 1 minute. Transfer to bowl with corn. Stir in mayonnaise and 1 1/2 cups of shredded cheese.
Pour mixture into a pie dish and sprinkle remaining 1/2 cup cheese over top. Bake until dip is heated through and cheese is melted on top, about 20 minutes. Serve hot with tortilla chips.
