Preheat oven to 400 degrees.
Form ground chuck into 1/2 lb round patties approximately 1/2" thick and slightly larger than brioche buns. Season heavily with salt and pepper on both sides.
Line baking sheet with parchment paper and lay bacon out in strips. Cook in oven for approximately 15 minutes or until crispy. Remove bacon to a plate lined with a paper towel.
Heat skillet on medium-high heat or pre-heat grill on high. Cook patties on both sides approximately 4 - 5 minutes per side. Brush melted unsalted butter on patties after flipping. Top with bleu cheese 1 minute before burgers are finished.
Lightly oil brioche buns. Season each side of brioche with salt and pepper. Place on grill or skillet and toast buns until golden brown.
Add mayonnaise and sriracha to a small bowl and stir until well combined.