Slice mini bell peppers into rings and remove seeds.
Add oil to preheated cast iron and cook the bell pepper rings. Flip halfway through so you get a nice char on each side. Once cooked, set bell peppers aside.
In a non-stick pan or enameled cast iron, cook the chorizo all the way through.
Once chorizo is cooked, add beaten eggs. Stir often until the entire mixture is cooked through, then add bell peppers back in.
Turn off heat and add shredded cheese, stirring to incorporate it and melt it throughout the mixture. After adding the melty cheese, grate some Cotija crumbles into the skillet and continue mixing.
Serve in a bowl with more grated Cotija crumbles and your choice of garnish. Or, use as filling in a breakfast burrito or breakfast tacos.