Bring a large pot of water to boil on your camping stove. Scramble your eggs in the zip baggie and add the ham or bacon. Zip the bag closed and drop into the boiling water. Boil and cook the eggs, turning the baggie occasionally, until you can no longer spot any runny egg in the bag (about 10 minutes).
While your eggs are cooking, prepare the English muffins. Gently break them apart and spread each half with butter. Heat a small pan on your other camping burner and place the English muffins butter-side-down in the pan. Cook until the muffins are browned. Remove from the pan and toast the other muffin. Top each muffin bottom with the mashed avocado.
When the eggs are cooked through, open the zip and slide the cooked egg onto a plate. Cut into two pieces and place on top of the avocado. Top each egg muffin with cheese and put the other half of the muffin on top.
Place the breakfast sandwiches back into the pan, place the lid on top and heat them on low until they are sufficiently warmed and the cheese has slightly melted. Add salsa, if you’d like. Devour immediately!