Chicken Curry without chili acorn

1 lb boneless skinless chicken breast , cut in 1 1/2 inch cubes 1/2 teaspoon salt 1/4 teaspoon pepper 1 tablespoon vegetable oil 1 onion , sliced vertically 3[...]

2 1/2 teaspoons coriander seeds 2 teaspoons cumin seeds 1/8 teaspoon red pepper flakes , crushed 1/2 teaspoon turmeric 1/2 teaspoon ginger , ground 1 pinch[...]

1/4 cup unsalted butter 1 medium onion , finely chopped 2 cloves garlic , finely chopped 1 tablespoon finely chopped peeled fresh ginger 3 tablespoons curry[...]