PREP: Marinate the chicken: Combine the chicken, yoghurt and half the masala paste into a bowl. Season with salt and pepper and stir to combine together. Cover with plastic wrap and let marinate in fridge for 2 to 3 hours
COOK: Heat oil in pan on medium heat. Add onion, garlic, chilli and ginger. Cook for a couple minutes until onion becomes translucent. Add remaining curry paste, cooking for a minute until fragrant and aromatic.
Add marinated chicken to slow cooker, along with onion garlic, chilli, ginger and curry paste mixture. Stir through.
Add the chicken stock/broth, tomato paste and canned tomatoes to slow cooker pot and stir through. Slow cook on low for 8 hours.
Stir though the thickened cream, and lemon juice.
Make a cornflour slurry bu mixing the cornflour with water. Pour in and stir with a spoon for a couple of minutes until curry starts to thicken a little.
Garnish with coriander, and service with Jasmine rice, or for a low carb option, cauliflower rice.