Choose your substitute based on the dish—aji amarillo or Fresno for stuffing and fresh use; red jalapeño, serrano, or DIY blend for cooking; pickled jalapeños for raw toppings.
Prepare the substitute by washing and slicing or dicing as needed; drain pickled jalapeños if used.
Apply the recommended ratio (usually 1:1 fresh weight or specified amounts) adjusting heat to taste especially for the DIY blend and bird's eye chili.
For cooked applications, add substitutes early to allow heat to mellow and integrate; for raw uses, check texture and flavor after preparation.
Taste and adjust seasoning or heat intensity if needed before serving to ensure balance similar to rocoto pepper.