1. Heat olive oil in a skillet over medium heat. Add the onion and sauté until softened, about 3 minutes.
2. Stir in the garlic, chipotle peppers, chili garlic sauce, and tomato paste. Cook for 2–3 minutes to deepen the flavor.
3. Add the diced tomatoes, spices, vinegar, cocoa powder, sugar, and salt. Stir well to combine.
4. Simmer on low heat for 5 minutes, stirring occasionally, until the mixture thickens.
5. Transfer to a blender or food processor and blend until smooth (or leave slightly chunky for texture).
6. Let cool completely before storing in a glass jar in the refrigerator.
Notes
💡 Tip: For extra smoky flavor, add a pinch of chipotle powder or roasted ancho chili powder. This paste keeps for 1 week in the fridge or up to 3 months in the freezer.