Place the red bell peppers and eggplant pieces on a lightly greased baking sheet and bake in a preheated oven at 220°C (425°F), until you see bubbles on the surface and the skin darkens, about 20-25 minutes (*see a step-by-step photo in this recipe). Then remove from the oven, cover with a damp towel, and set aside for about 20 minutes.
In the meantime, heat one tablespoon of the oil in a saucepan. Add the onion and sauté for 2-3 minutes, until translucent. Then add the garlic and sauté for another 30 seconds, stirring frequently. Set aside.
Peel your roasted peppers and eggplant. Add them to a blender along with the onion mixture, and chopped pepperoni. Blend until smooth.
Transfer the mixture to a saucepan. Add the remaining oil and vinegar and simmer for about 30 minutes, or until the desired consistency has reached, stirring occasionally. Season with salt and pepper to taste.
Fill it into jars and seal with a lid. Store in the refrigerator for up to two weeks.
Nutrition is calculated automatically and should be used as estimate.