Heat olive oil over medium heat in a large pan.
Add the onion, carrots and potatoes, and cook, stirring frequently for 5 minutes.
Add the cauliflower florets, garlic, ginger and spices, and cook for 1-2 minutes, until fragrant.
Add the stock, cover the pan, and cook for 15 minutes, until potatoes are soft.
Remove lid and cook down until liquids are largely gone (5-10 more minutes), mashing the mixture as it cooks.
Stir in the chickpeas and lemon juice.
Allow mixture to cool slightly before folding the samosas.
To BakePre-heat oven to 425°F. Line two baking sheets with parchment and set aside.
Cut a 6 inch egg roll wrapper to make it perfectly square, then cut in half to make two triangles.
Spoon 1-2 tablespoons of filling in the middle, then brush the edges lightly with water.
Fold the triangle over on itself, pressing firmly to seal. Repeat with remaining edge, and place on prepared baking sheet.
Repeat with all remaining samosas, until no filling remains.
Brush samosas with beaten egg, then bake for 12-14 minutes, until slightly golden and crispy.
Store in the fridge for up to 5 days.
To freeze:Cool samosas completely, then place on a baking sheet and freeze for one hour before transfering to a large freezer bag. Freeze for up to 1 month.
To re-heat:Microwave for 20 seconds fresh from the fridge, or multiple 30 second increments if re-heating from frozen.