Preheat oven to 400 degrees F. Line a baking sheet with parchment paper; set aside.
In a large bowl, combine ground beef, taco seasoning, tomato paste, 2 tablespoons chopped chilis, egg, breadcrumbs and chopped cilantro. Form into 2-inch meatballs and place on prepared baking sheet.
Bake for 15-20 minutes until cooked through. Remove and place each meatball in a corn chip scoop. Drizzle with queso, and top with guacamole, pico de gallo and chopped cilantro. Serve with a side of sour cream.
For the Queso:
In a large bowl, toss to combine cheddar cheese, pepper jack cheese and cornstarch. In a medium saucepan, bring milk to a simmer. Whisk in cheeses and chopped chilis. Bring to a simmer to thicken, about 1-2 minutes.