Heat a camping stove to medium-high and toast the crumpets (or English muffins).

Preheat a 10-inch cast-iron skillet, melting the butter. Add the Canadian bacon slices, and cook until lightly browned, about 2 minutes per side. Remove the bacon slices from skillet, and set aside.

In the same skillet add the eggs, and cook, without stirring, until the eggs start to set on bottom. Continue cooking, stirring occasionally, until desired degree of doneness. Salt and pepper to taste.

Stir together the mayonnaise, lemon juice, and smoked paprika. Place one bacon slice on the toasted side of each of four muffin halves; top evenly with cooked eggs. Top each with one tomato slice, another bacon slice, and a dollop of lemon mayonnaise. Cover with the remaining muffin halves, and serve immediately.