And it's a thing of beauty.

"It's only in the family.".In Ubud, Bali, I found a shop called Hot Mama Sambal that sold sauces from all over the country, including a West Javanese one with tiny anchovies.

In the rugged but placid mountains near the northeastern tip of Sulawesi, I tasted a sambal cakalang of chiles, shallots, garlic, tomatoes, and smoked skipjack tuna, all deep-fried together, ground, and then refried to absorb the oil.It was so full of flavor—heat, sweetness, meaty depth—that I would've been happy just to eat it on plain rice (with krupuk, of course)..In North Sumatra, I sampled a sambal that upended everything I thought I'd learned.

It was just green chiles, salt, and andaliman, the juicy green local relative of numbing Szechuan peppercorns, pounded together.This sambal was powerful and almost overwhelmingly refreshing—an ideal complement to a fatty marinated pork dish beloved by North Sumatra's Batak tribes.

The 8.5 million indigenous Batak people are a mix of Christians and Muslims, but many retain traditional religious beliefs, with a special emphasis on the power of the number three: three primary gods, three primary colors (red, white, and black), and three flavors—spicy, salty, and sour.

"These three flavors are fundamental to our society," said Rahung Nasution, a Batak chef and adventurer who led me through the region.plus 1/2 teaspoon kosher salt, divided, plus more to taste.

plus 1/4 teaspoon black pepper, divided.Granulated sugar, to taste.

8. bone-in pork rib chops, cut 1 to 1½ inches thick.Flaky sea salt, to taste.