I would post a recipe but I didn't measure anything. As usual I taste tested as I added ingredients. The serrano was too hot for either dish. The sauce for the potatoes was heavenly or at least would have been with 1/2 a serrano. I used olive oil, cream cheese, cheddar cheese, half and half, sour cream, onion, too much serrano pepper, garlic, salt and pepper and served it on boiled sliced yukon gold potatoes. The sauce was just the ingredients combined in a bender. It's a keeper with a bit less capsasin.
The stir fry is a fusion of Latin and Asian cuisine. The ingredients are pork tenderloin, onion, bell pepper, garlic, tomato, cumin, soy sauce and vinegar all stir fried in a wok. Oh did I forget the serrano pepper? No but I wish I had cut it in half. So you have meat, sofrito and soy sauce. What could go wrong?
The stir fry recipe calls for aji amarillo or yellow chili pepper but none was avaliable to me. It may be milder than the serrano and suit these dishes better. I don't know. I do know that I will make the dish again with a bit less capsasin. When I do that I'll work up a recipe.
There is plenty more to investigate into Peruvian cuisine. I'm certainly not finished with it.