Use either the 2 remaining sides of the sliced capsicum or the remaining slice of potato to cover the top. Then using a funnel pour a coffee cup of cold water into the tin. Add black pepper to your taste (optional).Then cover with foil totally and pierce two holes in the top for steam to release and place on the top shelf of a pre heated oven on highest heat for ten / fifteen minutes then reduce heat to electric cooker 2 or gas 2/and a bit. Look for a further 60 minutes. Be careful when removing from oven. You can test by removing from oven and use a fork once you have lifted a bit of the foil to see whether the potato (by sticking a fork in) is cooked or not to your own satisfaction. Please be careful removing hot items from ovens. Wear oven gloves or something similar. When the food is ready, use the flaps created with the foil to carefully lift the food out of the tin onto the plate and gently tear the foil under the food.