In a skillet, heat oil over medium heat. Add chopped onions and garlic to the pan and sauté for 2-3 minutes.
Toss in the chopped mushrooms and cook until fully done.
Add parsley, red chili powder, and salt & pepper to the pan and mix well. Let the mixture cool for a few minutes.
Once the mixture has cooled, add grated Swiss cheese and fold it into the mixture.
Take a samosa pastry sheet and fold it in half diagonally to form a triangular shape. Put a spoonful of the mushroom & Swiss cheese mixture on one half of the triangle and fold the other half of the pastry sheet over the filling, sealing it with some water.
Use a fork to crease the edges of the samosa to seal it shut. Keep repeating the process until all your samosas are filled.
Finally, drop them in hot oil and fry until crisp and golden brown. Serve hot with your favorite dipping sauce.