Heat 1 tablespoon oil in a large frying pan or skillet over medium-high heat.

Add chicken thighs in a single layer.

Let the chicken brown on both sides.

Transfer to slow cooker.

Add onions, ginger, garlic, bay leaves, ground cumin, garam masala, red chili powder, butter, lemon juice, tomato paste, yogurt, coriander (cilantro) leaves and water.

Stir to combine. Season with salt and pepper.

Cover and cook over low heat for about 5 hours or until cooked through.

Remove chicken from slow cooker.

Cut chicken into smaller pieces and return back into slow cooker.

Add cream.

Stir to combine.

Simmer for 2 minutes. 

Garnish with more coriander (cilantro) leaves.