Start by spraying your casserole or baking dish with non-stick spray and removing the crust from your bread slices.
Butter your bread slices no both sides. It may be easier to melt the butter and brush it onto both sides rather than spread it. Cut into large cubes and set aside.
Add an even layer of chorizo at the bottom of your casserole dish. Add bread and cheese over the chorizo.
In a medium size mixing bowl, whisk together your eggs, milk, mustard powder, salt, and pepper. Top with another layer of cheese, cover, and let rest for as long as 8 hours. If you’re in a jam no need to let it rest. Just that the casserole will hold together better this way.
When ready to bake, preheat the oven to 350°F. Uncover and bake 45-60 minutes. Remove from the oven when the cheese is melted and eggs are fully set. Allow to cool for about 10 minutes.
To serve garnish with red salsa and fresh cilantro.
Substitute chorizo for your favorite soy-based protein, Soyrizo will be just as good.