Heat a pan over medium heat and cook the chorizo until fully browned. Drain any excess fat if any. Add the onions and cook until softened.
Whisk the eggs and egg whites in a bowl, season with salt and pepper. Pour them into the pan with the chorizo and onions. Cook, stirring occasionally, until the eggs are set.
Tuck and roll. Place the filling (about 1/2 cup of the chorizo mix) in the center of the tortilla, leaving some space around the edges. Fold in the left and right sides toward the center, then start rolling from the bottom up, keeping it tight as you go.
Seal it up. Once rolled, press gently to keep everything in place. If you want extra security, toast the seam side down in a pan for a few seconds to seal it shut.
Notes
The calories are calculated on using Mission low carb tortillas and no cheese.