Chicken Curry with lemon

1 onion , roughly chopped 1/3 cup tomato paste 1/3 cup roasted cashew nuts 2 teaspoons garam masala 3 garlic cloves , chopped 1 tablespoon lemon juice 1[...]

2 tablespoons butter 1 cup chopped onion 1 cup chopped peeled apple 1 (16 ounce) can stewed tomatoes , with their juices 1 cup chicken broth 1 teaspoon lemon[...]