Take chicken in a bowl. Add salt and crushed peppercorns and mix well.
Heat olive oil in a non-stick pan. Place chicken pieces in it, in single layer, making sure sides of chicken pieces do not touch and sear for 4-5 minutes from all sides. Remove from the pan and set aside.
In the same pan, add onions and sauté on medium heat till golden.
Add ginger-garlic paste, cardamom powder and cinnamon powder, mix well and cook for 1 minute, stirring continuously.
Add ground walnuts, mix well and cook for 2-3 minutes, stirring occasionally.
Add pomegranate juice, lemon juice and lemon zest, stir to mix and cook for 2 minutes.
Add chicken, mix well and bring to a boil. Reduce heat, cover and cook for 30-35 minutes or till the chicken is fully done.
Remove the chicken from the pan
Remove chicken from pan and cover to keep warm.
Reduce the walnut sauce until it reaches the desired consistency. Add chicken, mix well and switch off heat.
Transfer onto a serving plate. Garnish with pomegranate pearls and mint leaves serve immediately.