Preheat oven to 375F.
Add both cheeses to a 6-inch cast iron skillet and toss together. Place in the oven and bake until melted and bubbly, about 15 minutes. Turn the oven to broil and cook for 3-4 minutes longer or until the top is golden brown.
While the cheese melts, dice the tomatoes into 1/4-inch pieces. Place the diced tomatoes onto a paper towel to soak up any extra liquid.
To serve top the melted cheese with diced tomatoes, green onions and cilantro leaves. Serve immediately with tortilla chips for dipping.
Recipe Courtesy of Megan Mitchell