Preheat your oven to 400°F (200°C). Place the chopped red bell pepper on a baking sheet and roast for 10-15 minutes, or until slightly softened and lightly charred. This step adds depth of flavor. (Alternatively, you can skip roasting and add it raw to the food processor.)

While the pepper roasts, prepare your chilies, garlic, and red onion.

In a food processor or high-speed blender, combine the roasted red bell pepper, red chilies, garlic, red onion, olive oil, red wine vinegar, lemon juice, smoked paprika, dried oregano, salt, and black pepper.

Process until the mixture is very smooth. If the sauce is too thick to blend properly, add water 1 tablespoon at a time until you reach your desired consistency. For a marinade, a slightly thinner sauce works best to coat evenly.

Transfer the blended sauce to a medium saucepan. Bring the sauce to a gentle simmer over medium-low heat. Cook, stirring occasionally, for 15-20 minutes. This step allows the flavors to meld and intensify, and helps mellow the raw garlic and onion notes.

Taste the sauce and adjust seasonings if needed. You might want more salt, a bit more lemon juice for tang, or even a pinch of sugar (optional) to balance the heat.

Remove the sauce from the heat and allow it to cool completely before transferring it to an airtight jar or bottle. Once cooled, it's ready to use as a marinade or as a fiery condiment.