Preheat the oven to 260C/500F, you want to get the oven very hot.
Wash and clean the red peppers, pat dry. Place the peppers whole on a sheet pan. Put the peppers in the oven for about 45 minutes, or until the skin becomes wrinkled and outer layers appear charred. After every 15 minute interval, you should turn the peppers to evenly char all the skin.
After the peppers are charred, remove from heat and wrap them in aluminium foil. Set aside for about 40 more minutes. When you open the aluminium foil, the peppers should be cool enough to handle, but still warm.
Peel the red peppers by removing the charred skin. Cut in half and remove the seeds and stems. Slice the peppers into desired size (chunks, strips or halves), and place into a bowl. Pour the olive oil over the peppers and sprinkle with salt. If you want a garlic flavour, add chopped garlic.
Store in a sealable container or jar in the refrigerator for up to three weeks. Serve in salads, sandwiches or as a side dish.