Preheat broiler with rack in top third of oven. Melt bacon fat in a large skillet over mediumhigh heat. Add scallions and chile and cook, stirring, 1 minute. Add corn and salt and cook, stirring, 1 minute.
Whisk together eggs in a large bowl and stir in chips. Add to skillet with corn and cook, stirring, until bottom starts to set but is still wet, about 1 minute. Stir and transfer to a broiler-proof 8-by-11 1/2-inch baking dish; broil until eggs are set, about 2 minutes. Scatter cheese on top and let stand 10 minutes. Garnish with cilantro sprigs and serve with chips (tuck some into the top), avocado, and tomatoes.