In a mixing bowl, combine flour, salt, vegetable oil, and water. Mix well until a soft dough forms that leaves the sides of the bowl. You may need to add a little more flour.

Knead the dough on a well-floured surface for a few minutes. Cover it with a bowl and let it rest for 20-30 minutes.

Knead the dough again for a couple of minutes. Divide it into 16 equal portions and roll them into small balls.

Allow the balls to rest for a few minutes, then roll each into 6 or 7-inch circles on a floured surface. Cut each circle in half.

Dice the potatoes into ¼-inch cubes and boil them in salted water until fork-tender. Be careful not to overcook them. Drain and set aside.

In a large skillet, heat vegetable oil. Cook the diced onion and garlic over medium-low heat until softened. Increase heat to medium-high, add ground beef, salt, and pepper, and cook until the beef is browned. Break it up into small pieces while cooking.

Remove from heat and mix in boiled potatoes, garam masala, curry powder, chili powder, Chinese five spice powder, cardamom, and fenugreek. Allow to cool before stuffing the samosas.

Brush the edges of the semi-circles with an egg wash made from whisking together 1 egg and 2 tablespoons of water.

Place a heaping tablespoon of the beef filling in the center of the half-circle. Fold the curved sides over the filling, pinching the bottom to seal.

Fold the straight edge down to create a triangle shape. Dust the uncooked samosa with flour and place them on a parchment paper-lined baking sheet.

In a deep pan, heat vegetable oil to 325 degrees F. Fry the samosas until golden brown.