1) Preheat the oven to 190C/Gas 5.
2) Heat a skillet over medium-high heat and add the almonds and toast swirling the pan until golden. Remove almonds and set aside, reserve skillet.
3) Season the chicken all over with salt and pepper. Dredge the chicken in flour and shake off any excess. Heat the oil and butter in the skillet over medium high heat. Cook the chicken on both sides until golden brown, about 8 minutes. Transfer to a dish and set aside.
3) Add the onion, capsicum, garlic, curry powder, thyme, and cayenne to the pan. Stir to loosen up the brown bits on the bottom of the pan. Cook until the vegetables are tender, about 5 minutes. Stir in the tomatoes and nestle the chicken pieces in the sauce, bring the sauce up to a simmer and then transfer to the oven and cook until the chicken is cooked through and tender, 20 to 25 minutes.
4) Remove skillet from the oven and transfer chicken to a serving dish. Spoon any oil off the surface of the sauce and discard. Bring the sauce to a simmer over medium heat, add the currants and simmer to thicken slightly. Season with salt and pepper, to taste. Spoon the sauce over the chicken and scatter the toasted almonds on top. Serve with a dollop of cool yoghurt and herb sauce.
5) For the yoghurt and herb sauce: In a bowl combine the first 4 ingredients, season with salt and pepper, to taste.