Salsa Roja

Method

1. char14 min
   dry comal or cast iron, medium-high, no oil
   tomatoes + onion slices + jalapeños + unpeeled garlic, turning every few minutes until the tomato skins split and blacken in patches and the garlic gives under a thumb. No oil and no crowding: the pan has to stay hot enough to drive water off the skin, because until the surface is dry it steams rather than browns and you get pink raw-tasting salsa. Pull the garlic first — bare cloves scorch in a minute and turn acrid.
2. toast1 min
   same dry pan, medium
   guajillos + ancho, pressed flat, 20–30 seconds a side until they puff slightly and smell like raisins and cocoa. This is the step most recipes skip and the one that makes the sauce taste of chile rather than of tomato paste. Watch it: a chile that goes past fragrant to smoking is permanently bitter, and one burnt chile poisons the whole batch — there is no correcting it with salt or sugar.
3. infuse15 min
   boiling water, covered, off heat
   toasted chiles + boiling water, weighted under a small plate so they stay submerged and soften evenly. Drain and discard the soaking water — the ancho skin leaches tannin into it, and adding it back is the usual reason a homemade salsa tastes harsh at the back of the throat.
4. peel2 min
   slip the garlic out of its skins and pull the blackest flakes off the tomatoes, leaving most of the char. Stems off the jalapeños; leave the seeds in for heat or scrape them out for a milder sauce.
5. mix3 min
   blender, short pulses
   drained chiles + charred tomatoes with their juice + onion + garlic + jalapeños, pulsed to a loose purée with visible flecks. Run it smooth and continuously and you whip air in, which lightens the color to orange and thins the body; short pulses keep it brick red and spoonable.
6. season2 min
   off heat
   + salt + lime juice, then taste and rest a few minutes before judging — salt takes a moment to travel through a purée, and charred tomato reads sweet at first and only shows its acidity once the salt lands. Add optional cumin, cilantro or a pinch of sugar last; sugar is a correction for underripe tomatoes, not an ingredient.