veganRinse and dry
Rinse the Roma tomatoes, Serrano chiles, white onion, and a small handful of cilantro under cool running water, then pat them dry so they char instead of steaming.
Prep the aromatics
Peel the garlic clove and cut the onion into 2 or 3 large pieces. Leave the tomatoes whole, and trim the chile stems if you want them easier to handle in the pan.
Char the vegetables
Heat a dry skillet over medium-high until very hot. Add the tomatoes, chiles, onion, and garlic, and char them, turning as needed, until the skins are blistered and lightly blackened and the onion is softened, about 8 to 10 minutes.
Blend the salsa
Transfer the charred vegetables to a blender jar, add the cilantro, and blend until smooth or slightly rustic, adding water a tablespoon at a time only if the blades need help catching, up to 2.5 tbsp total. Blend for about 30 to 60 seconds.
Cook the sauce
Heat the neutral oil in a saucepan over medium heat until it shimmers. Pour in the salsa carefully - it may sputter - and simmer, stirring often, until it darkens a bit and thickens slightly, about 5 to 7 minutes. If it becomes too thick, loosen it with a spoonful of water.
Season and serve
Stir in the fine salt, taste, and serve the salsa warm.
