• Preheat the oven to 240°C/220°C fan/gas mark 9.
• Chop the sweet potato into 2cm chunks (peeling optional). Place onto a large (lined) baking tray.
• Drizzle with oil. Season with salt and pepper and then toss to coat. Spread out in a single layer.
• When the oven is hot, roast on the top shelf until golden, 20-30 mins. Turn the tray halfway through.

TIP: Use two baking trays if necessary.

• Trim and thinly slice the scallion, keeping the white and green parts separate.
• Peel and grate the garlic (or use a garlic press). Zest and quarter the lime.
• Halve the bell pepper and discard the core and seeds. Chop into 1cm chunks.
• Drain and rinse the beans in a sieve.
• Stir the coconut milk (or shake the packet) to dissolve any lumps.

• Place a large pan over medium-high heat with a drizzle of oil.
• Once hot, add the prawns, white of the scallion and bell pepper. IMPORTANT: Wash your hands and equipment after handling raw prawns. Prawns are cooked when pink on the outside and opaque in the middle.
• Season with salt and pepper and fry until soft and sweet, stirring occasionally, 4-5 mins.
• Add the garlic and garam masala and fry until fragrant, 30 secs.

• Add the chopped tomatoes, beans, 100ml water (per 2P), stock and the coconut milk.
• Stir until everything is well combined.
• Bring the stew to the boil.
• Cover and simmer for 8-10 mins.
• Season to taste with salt and pepper.

• Remove the pan from the heat.
• Stir in the roasted sweet potato.
• Add the lime zest and a squeeze of lime juice.
• Taste and season with salt, pepper, sugar and more lime juice if desired.

TIP: Loosen the stew with a splash of water if you feel it's too thick.

• Spoon the prawn and sweet potato stew into bowls.
• Serve any remaining lime wedges alongside. 
• Finish with a sprinkling of green scallion.