In a large skillet, cook the breakfast sausage over medium heat until crispy, about 5-7 minutes. Stir in the flour and cook for 2-3 minutes. Gradually whisk in the milk, season with salt and pepper, and cool slightly.

In a nonstick pan, scramble the large eggs until desired texture, seasoning lightly. Set aside.

In a mixing bowl, combine the flour and salt. Cut in the shortening and butter until crumbly. Mix the egg, vinegar, and water; add to the flour mix until a cohesive dough forms.

Roll out half the dough to 1/8-inch thick and cut into 3x4-inch rectangles. Place half on a baking sheet.

Brush edges of each rectangle with egg wash. Layer scrambled eggs and sausage gravy, then top with another rectangle, sealing edges.

Preheat oven to 375°F. Brush tops with egg wash, sprinkle cheese and season as desired. Bake for 25-30 minutes until golden brown.

Remove from oven, cool for 10 minutes and serve, or store in an airtight container.