This sauce was AWESOME! I didn't use the steak recipe, so I cooked the sauce in a pan that I had cooked bacon in...you know that tasted GOOD! My husband won't stop talking about it, I think I'll be making it again!
Saute onions in 4 tablespoons butter over high heat. Cook for 5 to 7 minutes, or until dark and caramelized. Reduce heat to simmer and pour in cream. Cook for 3 to 5 minutes, or until reduced by half. Stir in blue cheese until melted. Serve steaks on generous portion of sauce.