To make filling, season meat with salt and paprika.
Heat oil in a skillet; fry meat 15 minutes, turning frequently.
Let cool.
Peel onion; chop finely.
Finely chop green peppercorns.
Preheat oven to 400°F (205°C).
Combine mustard, rosemary, sage, onion and peppercorns in a small bowl.
Spread mixture over cooled meat.
Grease a baking sheet.
To make yeast dough, prepare hot roll mix with warm water and egg according to package instructions.
On a floured surface, roll out dough to a rectangle large enough to enclose meat.
Place meat on dough and fold dough over carefully to cover it completely.
Press edges together firmly to seal.
Place loaf seam-side down on greased baking sheet.
Brush with milk.
Bake 35 minutes or until a rich golden brown.