Wash wings and dab dry. Mix ketchup and oil in a bowl. Season with salt and pepper. Turn wings in it. Wrap 1 slice of bacon around each wing.
Place the wings side by side on a baking tray lined with baking paper. Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: see manufacturer) for approx. 35 minutes. Remove wings from the oven and serve with mango chutney.