01 -
Preheat the oven to 175°C and lightly oil a 23x33 cm baking dish. Set aside.
02 -
In a large skillet over medium-high heat, cook the sausage, breaking it up until it is fully browned. Drain the sausage with a slotted spoon onto paper towels, leaving the fat in the skillet.
03 -
Reduce heat to medium and melt butter in the skillet with the sausage fat. Whisk in flour, salt, and pepper, cooking for approximately 2 minutes to form a roux.
04 -
Gradually whisk in the whole milk and bring the mixture to a simmer. Continue cooking, stirring frequently, until the gravy thickens, about 5 minutes.
05 -
Pour the sausage gravy into the prepared baking dish. Cut each biscuit into quarters and evenly distribute them on top of the gravy.
06 -
Bake in the preheated oven for 25 to 30 minutes, or until the casserole is bubbling and the biscuits have turned golden brown.