Whisk eggs, salt and pepper in a large bowl.

Heat oil in a large nonstick pan over medium-low heat. Add serrano and paprika; cook, stirring frequently, until fragrant, 1 to 2 minutes. Add spinach; cook, stirring occasionally, until wilted, 1 to 2 minutes. Pour in the eggs and cook, stirring occasionally, until the eggs are mostly set, about 5 minutes,

To assemble burritos, place each tortilla on a sheet of foil. Add ½ cup scrambled eggs to the bottom half of the tortilla, then divide cheese evenly (about 1 tablespoon + 1 teaspoon per burrito). Roll snugly, tucking in the ends as you go. Wrap tightly in the foil and freeze for up to 3 months.

To reheat, unwrap a burrito and transfer to a microwave-safe plate. Cover with a paper towel and microwave on Medium (or 50% or Defrost) for 1 to 2 minutes. Microwave on High until heated through, about 2 minutes. (Alternatively, bake foil-wrapped burritos at 375°F until heated through, about 25 minutes.)