Shrimp and spinach biryani

Ingredients

• 1 398ml can chopped tomatoes
• 2 tbsp canola oil
• 1 large onion (halved and thinly sliced)
• 1 red chili pepper (deseeded and thinly sliced)
• 1/2 oz fresh ginger (peeled and finely chopped)
• 1 tbsp ground cumin
• 1 tbsp ground coriander
• 1 tsp ground turmeric
• 1/2 tsp ground nutmeg
• 1 cup basmati rice (rinsed)
• pinch sugar
• 6 2/3 cups baby spinach leaves (roughly torn)
• 1/2 lb raw shrimp (peeled, thawed if frozen)