In an Instant Pot, heat oil on the sauté setting. Add cumin seeds and coriander seeds, cooking until fragrant, about 30 seconds.

Stir in chopped red onion, diced green chili, and cashews; sauté until the onion softens, around 5 minutes.

Mix in ground turmeric, ground cumin, ground coriander, cayenne, and minced ginger.

Add cubed potatoes and water, sealing the lid and cooking on high pressure for 5-6 minutes.

Release pressure naturally and mash some potatoes before stirring in peas, chopped cilantro, chopped mint, and lemon juice.

Adjust seasoning and cool.

While the filling cools, preheat your oven to 400°F (205°C) and prepare the vegan puff pastry.

Roll out the thawed pastry until it's about ¼ inch thick, then line a baking sheet with parchment paper.

Transfer one sheet of the pastry onto the baking sheet, leaving enough overhang.

Spoon the cooled vegan samosa filling onto one half of the pastry, leaving a 1-inch border.

Fold the pastry over the filling to create a half-moon shape and seal the edges.

Use a fork to crimp the edges and cut a few small slits in the top of the pastry.

Brush the top with a bit of oil or non-dairy milk.

Bake for 18-22 minutes, or until the pastry turns golden brown and flaky.

Allow to cool for about 5 minutes before slicing.

Slice and serve warm with your favorite chutney.