Cook the bacon in a cold skillet over medium heat for about 6-8 minutes until crispy. Transfer to a plate lined with paper towels.

In a bowl, whisk the eggs with salt. Heat a non-stick pan over low heat, melt the butter, and pour in the eggs. Cook gently for 3-4 minutes until fluffy.

Toast the bagels in a toaster or grill pan until golden brown for about 3-5 minutes.

Assemble the sandwich by layering cheddar cheese, scrambled eggs, crispy bacon, and chives on the bottom half of the bagel, then top with the other half.

Serve the sandwich warm with coffee or juice.