Grilled Pork Tacos, Pastor Flavors - Rick Bayless

Ingredients

• A 3 1/2 ounce package achiote paste
• 3 canned chipotle chile en adobo, plus 4 tablespoons of the canning sauce
• 1/4 cup vegetable or olive oil, plus a little more for the onion and pineapple
• 1 1/2 pounds thin-sliced pork shoulder (1/4-inch-thick slices are ideal—the kind Mexican butchers sell for making tacos al pastor)
• 1 medium red onion, sliced 1/4- inch thick
• Salt
• 1/4 of a medium pineapple, sliced 1/4-inch-thick rounds
• 20 warm corn tortillas
• About 1 1/2 cups raw tomatillo salsa