In a dry skillet over medium heat, toast the dried Chile de Árbol peppers for 1-2 minutes until fragrant and darker.

Add the Roma tomatoes, garlic, and onion to the skillet. Char them for about 5-7 minutes until the tomatoes are blistered.

Transfer the toasted peppers and charred vegetables into a blender. Add salt, water, and optional vinegar. Blend until smooth.

In the same skillet, heat the vegetable oil over medium heat. Pour in the blended salsa and cook for 5-7 minutes, stirring occasionally.

Taste the salsa and adjust seasoning if needed. Remove from heat and let cool slightly before serving.