Cook the diced potatoes. Preheat the oven to 430°F (220°C). Season the potatoes with salt, pepper, and smoked paprika. Add the oil and toss the potatoes. Add them to a lined roasting tray or sheet pan and add them to the preheated oven. Cook until crispy on the outside, about 35 minutes, using a spatula to flip them or move around the sheet pan halfway through.
Cook the chorizo. Heat a non-stick frying pan over medium-high heat (you don’t need oil as the chorizo will naturally release it). Take the chorizo sausages out of their casings and add them to the hot pan. Break them down into small pieces with a spatula while they’re cooking. Cook for about 8-10 minutes, until fully browned and no pink remains. If there’s excess fat/oil in the pan, drain the chorizo before adding it to the burritos.
Cook the scrambled eggs. Whisk the eggs with salt. To a non-stick frying pan over medium-high heat, add the butter. Once the butter has melted, add the whisked eggs. As soon as they start to set on the edges, push them to the center using a silicone spatula and fold over until just set but still soft.
Assemble the burritos. Warm up the tortillas. Warm up the tortillas slightly so they’re easier to wrap. You can either warm up each one for just 15-20 seconds on each side in a dry pan over medium heat. Or you can microwave the stacked tortillas on a plate for about 1 minute in the microwave with a damp paper towel on top to keep them soft. Add the fillings. Divide the fillings among the 8 tortillas. To each tortilla, add the fillings in this order: a bit of cheese, cooked potatoes, cooked chorizo, scrambled eggs, and more cheese on top. Optionally, if serving the burritos immediately rather than for meal prep, add avocado and tomatoes as well before adding the final layer of cheese. Wrap the tortillas around the fillings. Wrap the sides first over the filling, then fold over the bottom part over the wrapped edges and fillings (pulling the fillings in), then fold over and roll. Toast the burritos. Toast the burritos in a pan over medium heat, seam-side down first (so the cheese melts and holds the seam together).
Serve with salsa on the side. Or, if making them for meal prep, wait for them to cool down completely before refrigerating or freezing them.