Preheat the oven to 425°F. Line a baking sheet with aluminum foil. Arrange the bacon slices on the lined baking sheet in a single layer and bake for 25-30 minutes, or until crispy. Transfer the cooked bacon to a plate lined with paper towels to drain excess grease.

Divide the sausage mixture into four equal portions and shape each portion into a patty that's slightly larger than the slices of bread. Cook the sausage patties in a medium skillet over medium heat for about 3-4 minutes per side, until browned and cooked through. Place a slice of cheddar cheese on top of each patty to melt before removing from the skillet.

Wipe out the skillet and melt the butter over medium heat. Add the beaten eggs, salt, and pepper, stirring to combine. Cook until the eggs are thickened and no visible liquid remains, then remove from heat.

Spread 1 tablespoon of cowboy butter on one side of each slice of toasted bread. Assemble the sandwich by placing a sausage patty on one buttered slice, topping it with bacon, avocado slices, and about ½ cup of scrambled eggs. Place another slice of buttered bread on top, cut the sandwich into four triangles, and secure each with a toothpick.

Repeat the assembly process for the remaining sandwiches and serve immediately.