How to Make It
Preheat oven to 350°F. Spread the chili onto a rimmed baking sheet. Top with the Fritos, cheese, and half of the chopped tomatoes. Bake until warm throughout, 13 to 15 minutes. Remove from oven. Adjust oven rack to uppermost position and heat broiler to high. Broil until the cheese is fully melted and Fritos are browned in spots, 2 to 3 minutes.
Top with onion, jalapeños, sour cream, and remaining chopped tomatoes.