Bake the Tater Tots as the label directs and set aside. Reduce the oven temperature to 375 degrees F.
Meanwhile, cook the chorizo in a medium ovenproof nonstick skillet over medium-high heat until lightly browned, about 5 minutes. Transfer to a paper towel-lined plate and wipe out the skillet.
Whisk the eggs with the half-and-half, 1/2 teaspoon salt and a few grinds of pepper in a large bowl. Stir in the Tater Tots, cheese and scallions.
Melt the butter in the skillet and add the egg mixture, spreading it out with a rubber spatula. Scatter the chorizo over the top; transfer the skillet to the oven and bake until the eggs are set, about 30 minutes. Let stand 10 minutes, then slide onto a cutting board and cut into bite-size pieces.