Melt the butter in a medium saucepan over medium heat until bubbly and golden.
Whisk in the flour, onion powder, garlic powder, and pepper, cooking for 1-2 minutes until the roux is fragrant and slightly toasted.
Slowly pour in the beef and chicken broths while whisking constantly to prevent any lumps from forming.
Bring to a gentle simmer and continue to cook for 3-5 minutes until the gravy is thick enough to coat the back of a spoon.
Adjust the seasoning with extra salt or pepper to match your perfect flavor profile.
Serve immediately over a large bowl of creamy mashed potatoes for the ultimate comfort food experience.