In a small bowl, combine 2 tablespoons of mayonnaise, 1 tablespoon of sweetened condensed milk, and 1 teaspoon of Sriracha if you like a kick. Stir until smooth and well combined, then set aside.

Heat a skillet over medium-low heat and add 1 tablespoon of butter. Place 4 slices of white bread in the skillet and toast for about 2-3 minutes on each side until golden brown.

In the same skillet, add 3 slices of bacon and cook until crispy, about 4-5 minutes. Set aside on a paper towel to drain excess grease.

In a bowl, whisk together 3 large eggs, 1 teaspoon of milk, a pinch of salt, and a pinch of sugar. Add another tablespoon of butter to the skillet and pour in the egg mixture. Stir gently over medium heat until the eggs are just set and fluffy.

Spread the sauce on the inside of each toasted bread slice. Lay 2 slices of cheddar cheese on one slice, followed by the scrambled eggs and crispy bacon. Top with another slice of sauce-coated bread.

Slice the sandwich in half and serve immediately, garnished with parsley flakes.