First, you want to preheat your oven to broil. This high heat is crucial for roasting the peppers properly. While it heats up, wash your red bell peppers thoroughly. Then, cut each pepper into 3-4 sections, carefully removing the stem and seeds. Lay them out on a large baking sheet with the waxy side facing up. You want to ensure they’re spread out to roast evenly.
Next, place the baking sheet on the upper rack of your oven. Broil the peppers until the skins are mostly blackened, which should take about 15 to 20 minutes. The roasting process caramelizes their natural sugars, enhancing their sweetness.
After the peppers have charred, add the garlic cloves to the baking sheet. Return it to the oven for another 1 to 2 minutes to roast the garlic. You want it to turn soft and fragrant, complementing the pepper flavor.
Once done, carefully transfer the blackened peppers into a large paper grocery bag or a plastic zip bag. Seal it tightly and let the peppers steam inside for about 15 minutes. This steaming process will loosen the blackened skin, making it easier to peel.
While the peppers cool, grate the onion and carrot using a box grater. This will make them blend seamlessly into the sauce. In a large deep skillet or sauce pot, melt the butter over medium-low heat and add the grated veggies. Sauté until they are very soft and translucent, about 10 minutes. This will build a solid flavor base for your sauce.
Now, remove the cooled peppers from the bag. Carefully peel off the blackened skin, discarding it. You’ll be left with beautifully roasted peppers that are tender and full of flavor. Also, peel the roasted garlic cloves.
In a blender, combine the peeled roasted peppers and garlic. Blend until smooth, creating a vibrant puree that will form the heart of your sauce.
Pour the pureed mixture back into the skillet with the sautéed onion and carrot. Add the dried Italian seasoning, along with 1 and a half teaspoons of salt and half a teaspoon of ground black pepper. Stir to combine everything well.
Let the sauce simmer on low heat for at least 10 minutes. This allows the flavors to meld beautifully, and you can adjust the seasoning to your taste. Once done, your Roasted Red Pepper Sauce is ready to be enjoyed!