In a small saucepan, combine 2 tablespoons of maple syrup and 1 tablespoon of Dijon mustard. Heat over low heat, whisking continuously until the mixture thickens slightly, about 3 minutes. Once blended, remove from heat and allow it to cool while you prepare the other ingredients.

Place 8 slices of bacon in a cold skillet, then turn the heat to medium. Cook the bacon for approximately 10 minutes, flipping occasionally until it's crispy and golden brown. Once done, transfer the bacon to a plate lined with paper towels to absorb any excess grease.

In a mixing bowl, whisk together 4 large eggs, ½ teaspoon of salt, and ½ teaspoon of black pepper until frothy. Melt 1 tablespoon of butter in a nonstick skillet over medium-low heat, then pour in the egg mixture. Gently fold the eggs as they cook until they are just set and creamy, around 2 minutes.

Slice the croissants horizontally, creating a top and bottom half. For an added touch, lightly butter the cut sides and toast them in a skillet or toaster oven until golden brown.

On the bottom half of each croissant, generously spread the cooled maple mustard sauce. Layer with crispy bacon, a portion of the creamy scrambled eggs, and a slice of cheddar cheese. Top with the other half of the croissant.

Preheat your oven to 350°F (175°C). Place the assembled sandwiches on a baking sheet and warm them in the oven for about 5 minutes, allowing the cheese to melt beautifully and the sandwiches to heat through.