Mince 3 large garlic cloves and place in a 2-quart or larger slow cooker. Add 1 ¾ pounds boneless pork shoulder, ½ cup orange juice, ½ cup low-sodium chicken broth, 1 teaspoon ground cumin, 1 teaspoon kosher salt, 1 teaspoon black pepper, and 1 bay leaf. Cover and cook on the HIGH setting until the pork is fork tender, about 6 hours. (This is a good time to make the salsas.)

Arrange a rack in the middle of the oven and heat the oven to 400ºF. Quarter 12 ounces tomatoes and place in a small baking dish. Add 3 unpeeled garlic cloves, drizzle with 1 tablespoon olive oil, and season with 1 teaspoon kosher salt and 1 teaspoon black pepper. Bake until the tomatoes and garlic are soft, about 25 minutes. Meanwhile, prepare the green salsa.

Drain and halve 1 (11-ounce) can whole tomatillos and place in the blender. Coarsely chop ½ small bunch fresh cilantro leaves and tender stems until you get ½ packed cup and add to the blender. Squeeze the juice of ½ medium lime into the blender (about 1 tablespoon). Add 1 tablespoon olive oil, 1 teaspoon kosher salt, and 1 teaspoon black pepper. Blend until smooth. Taste and season with more kosher salt and black pepper as needed. Pour into a bowl, cover, and refrigerate until ready to use.

Finish making the red salsa: Remove the stems from 6 dried arbol chiles and place in a small bowl. Add enough hot tap water to cover and let them soak for 10 minutes. Meanwhile, wash and dry the blender.

When the tomatoes and garlic are ready, squeeze the garlic out of the skins into the blender. Add the roasted tomatoes and juices and soaked arbol chiles (leave the soaking water behind). Blend until smooth. Taste and season with more kosher salt and black pepper as needed. Pour into a bowl, cover, and refrigerate until ready to use.

Use 2 forks to shred the pork directly in the cooking liquid and toss to combine. Transfer to a bowl.

Finely dice ½ medium large onion (about 2 cups) and transfer to a medium bowl. Finely chop 1 bunch fresh cilantro leaves and tender stems until you have 1 packed cup and add to the onions. Toss to combine. Crumble 5 ounces feta cheese (about 1 ¼ cups).

Heat ⅓ cup of the canola oil in a 12-inch frying pan over medium-high heat until shimmering. Fry 16 to 18 small corn tortillas 2 at a time: Add to the pan and fry until light golde-brown and just starting to crisp, about 20 seconds per side. Spread about 2 tablespoons of the green salsa on top of each tortilla and continue to cook, very carefully basting with some of the hot oil, until the tortillas are golden and crispy around the edges, about 1 minute more.

Transfer the green salsa chalupas to a platter and top each with about 3 tablespoons pulled pork. Repeat making 6 more green salsa chalupas, adding more oil to the pan as needed. Wipe out the pan and repeat the process with the remaining oil and tortillas, this time using the red salsa. Garnish the chalupas with the onion and cilantro mixture and feta. Serve immediately.