Brown the sausage in a large skillet on medium heat until cooked through.

Using a slotted spoon, remove the sausage from the pan leaving the drippings behind.

Add the butter to the pan and melt, scraping up any browned bits with a whisk.

Add in the flour once the butter is melted and stirred into the drippings and give it a good whisk to combine.

Let the flour/butter mixture cook for about 60 seconds, then pour in the milk.

Gradually whisk in the milk, reduce heat to low, and cook until thickened - about 10 minutes.

Season to taste with salt and pepper. It's also really good with some crushed red pepper flakes on top if you like a little kick!