Preheat your oven to 400 degrees.
Put tortillas together and wrap them in a foil, let them warm in the oven for about 10 minutes or thereabouts. In a skillet preheated over medium-high heat, drizzle small olive oil, and once hot, add the sausage, cook, crumbling it with a wooden or a laden spoon as much as possible, and once cooked through, remove to a plate.
Clean out the skillet ( you can use a paper towel), drizzle oil, reduce the heat to medium, and cook the peppers (if you're using) and onion for 3 to 4 minutes or until tender, be careful don't let it get mushy. While they are cooking, whisk together the eggs with the milk and a pinch of salt and pepper, pour the mixture into the skillet with the cooked peppers and onions and cook stirring the whole time until the eggs are just set, stir in the cilantro and remove from the heat.
To assemble, add a spoonful of egg mixture in the center of each tortilla, followed by either the cooked sausage or black beans or everything from the above, add a sprinkle of cheese and a drizzle of hot sauce or salsa(if you're using). Wrap the tortilla burrito-style and pop them in the oven for about 5 minutes to warm everything through.
Tips: When wrapping the burrito, put a little bit of mayonnaise and spread on the tortilla (as shown in the above picture) to seal the end. Also, you can put the end of the wrap on a hot pan to seal it.