Heat a large skillet over medium-high heat. Add the butter, fresh corn kernels, garlic, and jalapeño. Cook, stirring occasionally, for 5 minutes. Transfer to a medium mixing bowl.
Add the mayonnaise, cotija cheese, cilantro, salt, and lime juice. Add the chili powder and optional ingredients if using. Mix until fully combined. Taste and season with more salt and mayonnaise if desired.
Garnish with chili powder to your liking, a lime wedge, and a sprinkle cotija cheese.
Serve immediately in individual portions.