Vegetables and cashew curry

700g pumpkin

1 medium (about 200g) green capsicum

medium (about 600g) cauliflower

1/3 cup oil

3 medium (about 450g) onions, sliced

5 cloves garlic, crushed

3 teaspoons grated fresh ginger

3 teaspoons curry powder

1 1/2 teaspoons turmeric

1 1/2 teaspoons garam masala

1 1/2 teaspoons ground coriander

2 1/2 teaspoons ground cumin

1 teaspoon sambal oelek

1 1/2 teaspoons yellow mustard seeds

1 1/2 teaspoons black mustard seeds

3 teaspoons vindaloo curry powder

1 tablespoon chutney

400g can tomatoes

2 cups water

300g broccoli, coarsely chopped

2 1/4 cups coconut cream

2 tablespoons chopped fresh mint

2 tablespoons chopped fresh coriander

1 1/2 cups unsalted roasted cashews