Preheat your oven to 425°F (218°C). Arrange the sweet red peppers on a baking sheet and roast for 20 minutes, turning them halfway through.

Once roasted, let the peppers cool slightly, peel off the skins, discard seeds, and place the flesh in a food processor. Add the garlic and pulse until roughly chopped.

Add olive oil, white vinegar, and kosher salt to the processor. Blend until reaching your desired consistency.

Transfer the blended mixture to a saucepan and simmer over low heat for about 30 minutes.

Remove from heat and let cool completely. Transfer to a glass container, seal, and refrigerate.