Step 1

Place split peas in a bowl and cover generously with cold water. Set aside to soak for 3 hours. Drain and rinse. Heat oil in a large saucepan over medium-high heat. Add onion and cook, stirring, for 3-4 minutes or until soft. Add garlic, ginger, mustard seeds and turmeric and cook, stirring, for 1 minute or until aromatic.

Step 2

Add split peas and stock. Bring to boil over a medium-high heat. Reduce heat to medium-low and cook, covered, for 10 minutes. Add sweet potato and cook, covered, for 15 minutes.

Step 3

Stir in peas and cook, uncovered, for 3-4 minutes or until split peas are tender. Stir in garam masala. Taste and season with salt and pepper. Set aside for 30 minutes to cool.

Step 4

Preheat oven to 220°C. Line a baking tray with non-stick baking paper. Cut each pastry sheet in half diagonally, then cut diagonally in half again (you should have 16 triangles). Divide sweet potato mixture into 16 equal portions. Place a portion of the mixture on 1 half of each pastry triangle. Lightly brush edges with a little whisked egg. Fold each pastry triangle over to enclose filling and press the edges together firmly with a fork to seal. Place on lined tray. Lightly brush the samosas with any remaining egg.

Step 5

Cook samosas in preheated oven for 12-15 minutes or until puffed and golden. Serve.