Sauté onions in a large skillet over medium-high heat until translucent, about 3-4 minutes. Do not overcook them; they’ll finish cooking in the oven. Add ground beef, garlic, Vegeta if using, salt, and pepper.
Simmer for 15 minutes and let cool. Beat the eggs with sour cream and mix with the ground beef and onion mixture.
Preheat oven to 375 degrees Fahrenheit. Grease a 9x13 baking pan generously with oil.
Lay the thawed phyllo dough sheets between two lightly damp kitchen towels.
Place two (three if extra thin) sheets of fillo dough into the prepared pan. Fold any excess dough in or cut with scissors. Brush or drizzle the top sheet with oil. Spread some of the meat filling evenly over the fillo, about 3 tablespoons. Repeat the layering process until the filling is used up, finishing with two-three layers of fillo.
Brush the top of the pastry generously with remaining oil. With a sharp knife, cut the phyllo pie into squares.
Bake for 45-60 minutes, or until cooked through and golden brown in color. Serve with buttermilk or Balkan style yogurt (like Greek) for authenticity.
~ Free Tip ~
Use melted butter instead of oil.
Try replacing onions with leeks for a different hint of flavor.