Heat a large skillet or dutch oven over medium-low heat 2-3 minutes. Add ground pork (pork should sizzle when added to the pan), 1/2 teaspoon of salt and 1/2 teaspoon of pepper. Cook pork, stirring occasionally, until crumbled and no longer pink. Remove pork from skillet and drain, reserving drippings (see note below).

Measure the drippings and return to the pan. Add enough butter to pan to total 5 tablespoons of fat. Sauté onions in drippings/butter over medium-low heat until tender (3-4 minutes).

Stir in remaining salt and pepper, crushed red pepper, sage and nutmeg and continue to sauté 2 minutes.

Sprinkle flour over onion mixture and whisk together.

Cook until bubbly and slightly browned (2-3 minutes).

Whisk in milk, a cup at a time, allowing gravy to thicken after each addition. Continue to heat, whisking constantly, until thickened. Remove from heat. Taste the gravy and add salt or pepper if needed.

Stir in ground pork and shredded cheese.

Cool gravy completely. Refrigerate overnight.

Preheat oven to 425 degrees.

Combine self-rising flour and greek yogurt in a large bowl. Gently stir (hands work great) until fully incorporated. Divide dough into 12 equal portions. Gently roll each between hands, place on a parchment-lined cookie sheet, press down lightly and brush tops with a little milk (this helps the biscuits to rise). Sprinkle each with coarse-ground salt and pepper.

Bake for 10-14 minutes until golden brown.

While biscuits bake, reheat sausage gravy over low heat. Add a quarter cup of milk for a thinner consistency, if desired.

Serve gravy over biscuits and top with additional shredded cheese and chopped green onions.